Three Points to Consider!
First, invented languages are actually, and in fact prominently on topic here in Worldbuilding! What Topics can I ask about here lists languages as a valid topic.
I suspect this was probably written before the invented languages forum got going. I have no problem with exporting all language invention questions to the other forum and no problem with inviting language related querents to ask their questions over there.
I just wanted to point out the glaring deficiency in the argument for this particular Policy before things get too far along! For this argument to make sense, someone should edit the help desk to reflect this Policy. Or perhaps, if needed, create a new Policy on Invented Languages query.
JBH has addressed this issue: First, the first point. I apologize because you're right that languages are listed in the help center. I also agree that its inclusion was certainly before Constructed Languages existed. So your point is well taken... but it's also irrelevant as we're really only focusing on a formal policy for "what's the best name for X?" questions. I admitted that I could be convinced otherwise about the process of naming and you've done a great job of doing that. focusing on rules should avoid the basic rule from the tour that Qs shouldn't seek opinions, but facts.
Second, I don't wholly disagree that questions that ask for names or for opinions about names or for advice on names should be considered off-topic here. While I don't see them as "story based" per se, I can certainly see how naming questions would turn into opinionfests, like the recent name my political system query. While I don't often VTC opinion based queries simply because some level of opinion generation is unavoidable in this forum, I did vote to close this one because it's obvious that the respondents aren't even close to consensus and I think that may be because the question wasn't well worded.
But I digress.
My point of disagreement with this Policy focuses on only one of the subparts, namely the lumping of the concept of naming in and of itself with concept of processes of naming.
My argument is that the process of naming a thing is essentially no different than the process of devising a thing. Both are processes of worldbuilding, and thus both valid. Their validity stems from the fact that the thing and the name are both artifacts of the world: matters of culture made by the people of that culture.
Conclusion: So I would agree with you that "What Do I Name This" kinds of questions are off topic. I would further agree that queries on pure advice, aesthetics, opinion seeking or euphonism -- basically cellardoorism -- are also off topic.
However, I disagree that process of naming queries ought to be considered off topic. An example of this kind of question might be:
Two cultures live side by side, A has access to trade routes with E, a distant & technologically advanced society, while B lives in a remote region and lacks contacts with any other culture apart from A, the people and culture of which B highly esteem. The people of cultures A & E are syringeal speakers (like birds) while the people of culture B are laryngeal speakers (like humans). Speakers of A can relatively easily pronounce the bimodal(two simultaneous vocalisms) language of E as well as the monomodal language of B; however the speakers of B, while they can understand the language of A, can not pronounce the bimodal syllables of A.
For reasons unimportant to the query, I want the speakers of B's language to borrow words from A's language. How can I reach a compromise between the two vocal systems such that a trade good from E, called {``srêê||,r~~~}{|-e|}{|`wi|} by the people of A, can be traded to the people of B who will give it a name recognisable to the traders from A. I'd like to preserve the overall structure of A's wordform, so answers like "well, they'll just give it their own name, so do whatever you want to do" are not admissible.
The notation of A's language: for purposes of this query, syllabic units that are divided by pipes denote a different vocalism emanating from left and right syrinx simultaneously; syllabic units enclosed within the double pipe denote both syringes are producing the same vocalism.
A third point to consider: Something else to think about re The name of something is always independent of the world's rules because any name can be used. Why one name is better than another is storybuilding because it only matters to characters in the story (not the world or any of its rules), and characters are off-topic per the help center.
Consider a world where semiotics, sound-symbolism and substantive onomotopoetics are operative rules of the place. I think it’s AlexP who’s fond of saying that words are not magic, but he is incorrect. Quite wrong indeed. In point of fact, here in Worldbuilding, words are not merely magic. Here, words not only create & define reality, but they also signal and represent the reality of the other world here within the real world.
In such a world as I propose for consideration, the very sound of a word relates to the form, composition and name of a thing. I mentioned cellardoorism as a concept earlier: the natural extension is phonaesthetic geopoetry. This is where the name of a thing is neither divorced from the rules or reality of the world, nor must it be made from a random opinion. This is not a case of any word will do, but rather the choice & crafting of word must follow reasonably logical rules, rational assumptions and must flow from the innate aesthesis of the world itself.
We do this in English a little bit by nature! If I said to you the sound sssssssss, I would probably lodge in your imagination images of sssslithery ssssnakessss and ssssneaky ssssspidersssessss, ssscorpionssss sssslinking in the darknesssss and ssslipery ssssputum and sssslime. What for us is a happy coincidence of a particular sound, [s:] and a particular set of concepts, chilly, dark, dank places filled with creepy crawly horrors is but the shallowest manifestation of this part of geopoetics.
I'll mention here that this can be a big stumbling block for a worldbuilder. I'd argue that a young worldbuilder or a beginner is more likely to have problems that could be solved by the mere application of opinion. Naming problems are often resolvable through individual or group brainstorming. Because "any name can be used".
And I certainly concur that WB is not for group brainstorming!
But as an example, this very issue has been a problem of worldbuilding for me. Over the last 30 to 40 years or so, I still have not hit upon the name for the race of people that more or less fulfill the role of Orc. The name of a whole race of people, as well as the constituent ethnoi, should fit. Any name can't be used, simply because they are not throw-away tidbits of background. In my opinion a well crafted world comprises not only objects, but also names. And the magic of words is that the name in a sense creates the object. If I've put the effort into naming an inconsequential a creature as the inverse earthworm, which are called hrratht.teth by those who have come across their deep telluric migrations, how much more consideration the name of "Orcs" deserves!