Some Considerations
This is a question of application of the Policy on Commercial & Third-Party Fictional Worlds. The basic policy is We have an unwritten rule that questions about commercial worlds (e.g. Star Wars, Star Trek, Babylon 5, etc.) should be asked on the Science Fiction & Fantasy stack; and its description and discussion can be read here. I think it is fair to say that the general consensus of the community is that this is a settled matter. We have a gentlesophont's agreement with the good folks over at SF & F where we send them queries about Marvel Comix and Lord of the Rings, and they send us stray questions about fictional worlds that don't fall within their bailiwick.
That said, the following is my take on your question as it relates to the named policy.
I. The rule, in enforcement, actually just forbids people from giving context to their questions about third party worlds. It is impossible to have an encyclopedic knowledge of every feature in every world, or to even know which world, if any, an idea came from. Hence, apart from well-known features of well-known worlds, it is only possible to find out about such a question if the asker says outright that it is about a third party world
I'd argue that the whole point of the rule is to prevent queries about third party worlds from being asked here in the first place. There is no good reason for anyone to have to "give context" about their third party world questions, because the proper forum for asking how such worlds behave is in fact SF&F. Questions about magic and technology and special powers of various races of people are commonplace there. For our part, we respect the boundary between "our own fictional worlds" and "JRR Tolkien's fictional world" by asking questions about the Silmarillion over there and our own fidgettywatties over here.
As for encyclopaedic knowledge, that's why we have SF&F! Their strong point is knowledge of the lore of any of hundreds of third party worlds. Some are very well known and part of common culture, others are so obscure that the only person who knows about them is the querent herself!
IJ. SciFi.SE, while it does allow questions to stray out of pure canon, is not WB.SE. It is based on the specific canon of a work, so I don't see them, for example, being able to tell the evolutionary history of a species seen only twice in a high-school dramedy that never once mentions evolution. Furthermore, SciFi.SE, from what I've read, is to assume normal science for the scientific questions, which is not useful if you're querying a world where you don't think normal science would fully apply in the area your question is about. For these reasons it is insufficient for querying new features for worlds
SF&F can and does engage in thoughtful and considered speculation. If you can name the world that high school dramedy is set in and name the creature, I'd put a penny to a pound that someone over there can give you a reasonable speculation based on what is known of that world. And if no canon description is available, because the Author did not provide one, and the matter is beyond speculation, because the Author did not provide enough background, they will tell you flat out that the question is not answerable. And that's your answer!
I think your point might possibly stem from a misinterpretation of what the two forums exist for. SF&F exists to give strongly factual or at least solidly conjectural answers to questions about third party fictional worlds. It's not their job to engage in wild speculation or to create headcanon or even to answer questions about one's own fanfic.
On the other hand, WB exists for the express purpose of helping anyone devise, construct or discover their own fictional world. We can give strongly factual, solidly conjectural, flimsily conjectural or even bonkozoid crazy answers to any question the writer or worldbuilder or geopoet might have.
That said, it is also not our job to cater to idle curiosity about a third party world. Questions such as the example evolutionary consideration you mention are simply as off topic here as it is in SF&F. This is because, WB has to at least try to conform to Stack Exchange's forum model. These kinds of questions lend themselves to being too broad, too opinion based (even for me!) and also quite literally can not be answered because there is no canon data upon which to formulate an appropriate answer.
Hence, the rule about sticking to your own work here in WB. If you ask a question about the evolution of some creature seen in a high school dramedy that you yourself wrote, we'll be able to provide you top notch answers. And the reason is quite simply because you are the author and only you can really determine which answer fits your world's circumstances best.
IJI. The justification that WB.SE isn't about how other worlds work doesn't hold up to scrutiny. No world is complete, and there are always more features you could add to someone's world. For example, let's you ask about the best way for the zekes from the Gone series could implement features from blue bats. The answers to this question would describe a unique idea, never seen in the series it is from. To declare this to be part of how that world works is like saying that building an extension is a contemplation of the house
I certainly concur: no fictional world is ever complete. (One could argue that the real world isn't even truly complete yet, let alone perfected.) And that is precisely why WB as a forum exists! To help folks on their path towards a world that is just a little less incomplete than it was before the question was asked.
However, you seem to be proceeding from a false presumption about this forum. Your presume that this forum, WB, exists to engage in idle speculation about somebody else's work. The Gone series of books was written by (I hazard the guess!) somebody other than you. The author's name is Michael Grant. You can read the books, you can examine fan sites, you can immerse yourself in lore related forums, you can look at the linked webpage, you can consider all the influences on his writing and you can privately speculate all you want on the conjunction of zekes and blue bats.
Interesting as that speculation assuredly is, it is off topic here in WB. If anyone were to post that question in WB, it would be closed for being off topic. They'd be invited to read the help center, refresh their memory by taking the tour, and perhaps even review what this forum is all about.
Such speculations and idle dreamthoughts do indeed have their place in worldbuilding! In the article on Worldbuilding Resources there is, under the heading Worldbuilding Discussion Forums, a number of highly interesting long & short form discussion groups where this kind of cross-over speculation can be engaged in.
IJJI. The rule is inconsistent with the rest of the rules: I have asked several questions about building up on an existing world, as I assume many others have too. This was allowed because said existing world was yet to be put out into the world. I cannot see any way that a world would be so different before and after publishing as to warrant this rule
Possibly the seeming inconsistency of the Policy evolves from a really bad misunderstanding or misinterpretation of 1) the Policy itself, 2) the nature of the forum it applies to and 3) the nature of the question's matter itself.
I know you have indeed asked many questions in WB! I've answered some of them! (And I hope I gave some help or inspiration to you, if not the very best answer you were looking for.) You've asked questions that we presume are about your own worldbuilding; and you've also asked questions about other people's worldbuilding. E.g., the example question about Michael Grant's zekes.
1 . The policy itself exists in order to separate and corral queries based on the forum's competency to answer. Math questions go to Mathematics, WWII questions go to History. In our case, Gone questions go to SF&F, while World of Ichthys King questions remain here in WB. Simply put, there's a division of labour in Stack Exchange, and to our lot falls queries about your own worldbuilding.
2a. The natures of the two forums in question are important to understand. SF&F clearly delineates what they are about:
Science Fiction & Fantasy Stack Exchange is for questions targeted towards science fiction and fantasy enthusiasts. This includes questions about:
Plot, character, or setting explanations
Historical or societal context of a work
Behind-the-scenes and fandom information
Story identification
Franchise/series reading or viewing order
2b. They are also clear as to what they are nòt about:
If your question is about...
Writing science fiction or fantasy, ask on Writers Stack Exchange.
Creating a fictional situation or universe of your own or investigating the plausibility of an element of another work of fiction, ask on Worldbuilding Stack Exchange.
3 . And before you cry aha! WB is about "investigating the plausibility of an element of another work of fiction!", this brings us to the nature of the question's material itself. Do keep in mind that that wording is taken from SF&F's help center, not WB's. Our own verbiage is much more creator-centric. For example, the goal of the site is to help you build your world. If it is your desire to understand the "plausibility of an element" within your own worldbuilding, we expect you to ask your question having already resolved the hows and whys of that element in its own context. This is because that material is not yours! It belongs to another geopoet, and we are not competent to answer on their behalf! Our job is to help you take your understanding of that element in the other Author's work and apply it to your own world. In order to do that, you would need to study that element and its context elsewhere. When you ask your question, you would need to post appropriate links to that external information, and then ask your own query about your own world. The situation is comparable to "real world questions". Generally speaking, they are welcome here, but with caveats. The querent needs to have already done some homework on the real world issue and they need to give appropriate background and context of their own world.
Summation:
I cannot see any way that a world would be so different before and after publishing as to warrant this rule
At last we get to the crux of the original question! The simple fact of the matter is that this Policy and its application quite literally have absolutely nothing whatsoever to do with the world itself!! You're quite correct in saying that there is no difference in a world --- qua mundo ipso --- before and after publication.
The underlying issue is that the Policy pertains to the geopoet herself as author & creator of the fictional world and not the world she has wrought.
For example, let's go back to the zekes. Gone is off topic here not because the world the stories are set in seems no different before and after publication, but simply because you, Ichthys King, are not that world's creator and are not that story's author. Nor am I. Nobody else in WB is either. The geopoet's name is Michael Grant. Michael Grant the geopoet, and by extension his corpus of work, is the only competent resource we have for settling questions about mutated wormlike creatures called zekes. Since Michael is not here in WB (that we know of!) to ask us questions about how zekes work, and since you are not the worldbuilder who has made the world the zekes inhabit, such questions are off topic here.
In a nutshell, the rule is warranted here because you're asking us to answer questions that you should be addressing to Michael Grant himself! The rule is warranted here because you're not asking us to help you understand or solve a problem with your own worldbuilding.
I guess that's two nutshells! I guess consider it a walnut and I really do hope that I've answered your concerns about the Policy in a sensible manner. I'm happy to clarify anything further and edit any factual errors as needed.
Follow-up Points
Your point about only asking on your own world isn't sensible. For example, let's say that while you are on a walk, you meet someone who decided (for some reason) to tell you about a magic creature she designed. She then goes on to say that her friend went to WB.SE to ask about if it could exist realistically. Would this scenario make you justified in seeking said question out and closing it for being off topic?
Furthermore, not all queries about third party worlds are specifically about canon, and can't all be best answered by the author. As an example, I doubt that Swift could give you a scientific explanation of the liliputians, even ignoring that he died in the 18th century –
Finally, framing third party questions as 'idle curiosity' is not an argument. I could just as easily say that asking about your own world is 'idle curiosity', and be just as wrong and hollow as you
This is a classic scenario that actually makes the argument in favour of the Policy in question, as well as in favour of other rules and customs of SE and WB specifically.
The claim that the rule is not sensible is a valid opinion. Rather than argue opinion vs opinion, if I were in that situation I'd simply recommend that the person join this great worldbuilding Q&A forum herself! End of story. I know that some people in this community would seek out and VTC the friend's question. I would not necessárily do that, as it would depend on how the question is worded. We rely on querents being honest in representing themselves as engaging in their own worldbuilding. If someone straight up said that they're asking on behalf of a friend, the community would be 100% justified in closing the question and inviting the person's friend to join so she can ask her own questions and evaluate the answers she receives based on her own worldbuilding work. This is a very simple and non-controversial policy.
Ultimately, all questions about third party fictional worlds boil down to canon. You bring up Liliputians: whether or not Swift could address a "scientific explanation" for that race or not, the fact remains that he is the only one who is truly competent to unequivocally evaluate an answer that explains them because, again, he is the geopoet that created the world the Liliputians inhabit.
It's never been proposed that all third-party world related queries are questions of idle curiosity. That's something you should address in another question. Suffice to say it is the custom of WB.SE to deny idle questions simply because they stray from the whole point of this forum and the askers of such questions are demanding an improper waste the time and effort of those of us who actually answer questions. If you want to ask an idle question about Liliputians, or anything else, I charge $75/hr for internet based research and $150/hr for book based research. If you're going to waste time on idle curiosity, you're at least going to make it worth my while to do your homework for you. Lastly, it is ever the case that those without good arguments always resort to ad hominem attacks or personal insult.
What do you reckon opinion based questions have to do with third party questions?
It's simple logic: If a question involving some canon is best answered by that canon, then it follows that a question involving opinion (i.e. all of them) is best answered by opinions, and so must be opinion based –
On the point of it being like the real world: I agree. So why must we bar questions that take elements from a third party world to make something new, when we allow questions that take elements from reality to make something new?
1 . That doesn't logically follow. "Canon" means the established facts of a fictional world or setting. Opinions aren't established facts of anything. Opinion based questions, at their worst, are simply a querent dredging the community for opinions -- what colour should it be -- what do you think this would look like -- which feature should I choose. They can be improved by the addition of context, focus and criteria.
2 . I think you're missing the point of the issue. On real world queries, facts are universal in nature and knowledge of them can be acquired from one's own experience, research and the expertise of others. No one here on Earth owns reality, so no person here on Earth is the competent authority to ask questions of. Answers can be judged, by the OP and by the Community, based on the corpus of human knowledge and wisdom.
On our own fictional worlds, the OP is not only the creator of the setting, but is also the keeper of all knowledge about the fictional world. The OP is the competent judge of all responses to her queries.
When it comes to third party worlds, I believe your initial assumption is incorrect. In this case, the creator of the setting and the competent judge of all queries is not the same person as the querent. We do not accept such question here because the querent can not judge the validity of the answers. Also, our express purpose in this forum is to help the querent build their own fictional worlds, not help them understand how somebody else's world works.
In the specific application of somebody else's work, a third party world, to the querent's own work, you have a valid point and my take is that there is no problem at all with asking a question of application of a third party world's elements to your own. However, there is an important caveat to understand. This is the underlying point of your original question; and I think it is also the stumbling block that you've set up for yourself in understanding how this forum works vs how other open ended forums work. Namely, Worldbuilding.SE is not the forum to ask this kind of research question in. As it happens, there is a very simple progression you can follow. The logical steps are:
First, do your own research. Like if you want to meld Ents and mermaids into one kind of creature, you would do your own basic research on those two topics.
Second, you would address any canonical queries re Ents in SF&F. That forum is where you could address questions of anatomy, physiology & evolution of Ents with respect to the lore of Tolkien's legendarium -- the canon.
Third, once you've got some understanding of you're working with, you are certainly free to ask queries of application queries here. For example, knowing that the Entwives have disappeared, and knowing that Ents are a kind of plantimal being and guardian force protective of the natural world, you might consider that the Entwives were driven from their terrestrial haunts and sought refuge in the sea. You could then ask about adaptation of your own Ent-like plantimal creature to a maritime environment, given X, Y & Z conditions of the world they inhabit and considering P, R & S constraints.
Following these steps will turn low quality brainstorming and opinion type questions into awesome queries of deep geopoesy, questions that will challenge the respondent and make the whole process satisfying and unfrustrating, questions that will set WB.SE apart from the open ended worldbuilding ruminations one finds on Reddit.
If it is solely based on who made the world/feature, then why are questions about dragons, mermaids, and unicorns so accepted as to have their own tags? No-one here made any of those creatures, yet everyone and anyone is free to ask questions about these and make judgements on the answers.
Yay! Progress! Precisely! This is because "dragons" and "mermaids" are not the distinct creation of any one individual. They are creations of human culture and are thus the common property of all humanity. It is precisely because no one made or owns those ideas that we can use them freely in our own worlds, modify them and ask questions about them here.
Why does the same not apply to more recently made worlds? Any justification I can think of for the former applies equally to the latter –
Now, Tolkien made use of this situation and created at least two named dragons, the more famous I'm sure being Smaug. So, asking if Smaug actually had a chink in his armour where he could be shot by this huge six foot long rod of iron as we see in the movie, that is a question for SF&F because Smaug belongs to JRRT and is governed by the canon of his legendarium. Asking about dragons in general, whether they have "armoured scales" and whether shooting them with long iron spikes might be a good way to slay them, that is an acceptable question for WB. This is because the querent is taking the same stock of raw materials that Tolkien took from and is creating her own legendarium, her own world.
Very simply, we don't answer questions about someone else's canon here. End of story. That is one reason why SF&F exists. Sorry, but all the justifications you might make simply run afoul of how Stack Exchange works.
Your line of argumentation is like the man set up a tiny house on the handicapped parking spots at Walmart, and, when questioned by the police gave the answer: but officer, everyone has the right to live in their own house, and this is my house. That line of argumentation misses the point entirely, because it ignores the fundamental point that the house is sitting on the handicapped parking spaces!
KeizerHarm: While I frankly agree with 95% of the things you have said here, I do agree with Ichtys that "only the author of a world can judge the best thing for a world" is a strange axiom, and I do not understand if it is rooted in your ethical values or in practical considerations. It is hard to hold when it comes to public domain works. You say that only Swift can judge competently what to do with Liliputians, does that mean that every movie adaptation of Sherlock Holmes is by definition incompetent, since they weren't made by Arthur Conan Doyle? Can Guy Ritchie visit this site?
That axiom is simply the logical distillation of how WB works. When you ask a question about a problem you're having with your own worldbuilding, I can write an answer in an effort to be helpful. I can perhaps try to inspire, to offer some levity or some creativity, but one thing I can not do is make the decision for you. No one else here can make the decision for you. When I try to do that, someone will (rightly) accuse me building your world for you. Note that the result of you judging the "best answer" for your world is that coveted green checkmark! Stack Exachange itself actually builds into the functionality of our forum the principle that only the querent can choose the "best answer", and this is done separately from the community voting on their favourite answer.
So, if only KeizerHarm can judge answers given for the world KeiserHarm made, and only Ichthys King can judge answers given for the world Ichthys King made, why should it be any different for questions & answers about the world that JRRT tolkien made, or the world JK Rowling made?
I agree with you on this: those worlds are, in a sense -- a cultural and non-legal sense -- part of the public domain. People dress up like Hogwarts students, they dress up like Hobbits and Elves, they dress up like Dr. Who characters of Marvel characters. They collect and make objects that come from those worlds. You can buy Harry Potter's official wand or Aragorn's official sword. Craftsmen and talented people make decorative and useful objects relating to those properties and people write stories and create games based on these popular worlds. To be frank, the only reason we don't take questions about those worlds is because SF&F exists as a forum! Can you imagine if we had to field all the questions about Harry Potter and Captain America and Tom Bombadil and Alice for people wanting to write fan fiction in those worlds if SF&F didn't exist!?
When I say "only Swift" can judge or "only Tolkien can judge", I rather thought it would be obvious that neither of those gentlemen would be actively and personally participating in these forums. We must therefore rely on -- canon. In Swift's case, that would involve the text of any of his works where Liliputians are mentioned (primary canon) and any of his papers or correspondence that talks about Liliputians (secondary canon). Tolkien is a much better example, because probably about 80 or 90 per cent of the secondary canon has now been published and probably 100% of his primary canon has been published. If you question about Tom Bombadil, you can read the narratives (Hobbit and LotR), and you can "ask Professor Tolkien" by the simple expedient of perusing CJRT's mammoth History of Middle Earth series, reading mentions made in his letters and checking into other major and minor works, like Silmarillion or the recently published Nature of Middle Earth.
As for legal derivative works (tertiary canon) -- essentially "officially sanctioned fan fiction" like Peter Jackson's movie adaptations, The Cursed Child and games like Hogwarts Mystery -- again, those are "worlds" created by an individual other than a person asking a question here in WB. This is why they're called "third party worlds". If Peter Jackson himself wanted to ask questions about Smaug here in WB, we would have closed his question for being off topic and would have sent him over to SF&F. Questions we have about those movies and other licensed properties are addressed in the appropriate forum.
Finally, as for legally grey derivative works (quaternary canon) -- essentially the fanfic I like to write about the wizarding world, or any of the Middle Earth derived worlds and cultures I've seen, and even including substantial works like The Last Ringbearer and Хранители / Khraniteli -- if you had a question about those, you'd also have to ask in SF&F because you're not asking a question about your own worldbuilding, but are asking about someone else's worldbuilding.
Lastly, if it's you doing the fanfic writing, and you have a question about some problem you're facing, I'd refer you to the Three Simple Steps process I laid out earlier for Ichthys King, as I think that would keep both forums neat, tidy and appropriately walled off from one another!