I read the question and I read kaya3's answer, in its original format and in its post-redaction version. Tortilena thinks I initially reacted too emotionally, and I concur, so am reviewing the whole matter again and am carefully rewriting my response.
Data & Commentary:
I've just reread the Meta question, all the answers and all the commentary. I've just reread the original Main query, all the answers and all the commentary.
OP asks a question about the mating habits of what is essentially an agendered but male-like, mitotically reproducing being that must make use of the female of another species as a receptacle for its baby zygote in order to reproduce.
The initial response under consideration makes assumptions about the motives and activities of the fictional race that have no basis in the query itself:
You are proposing (1) a biologically distinct race of humanoids which (2) does not coexist peacefully with humans, (3) can reproduce sexually with humans but the offspring are their own race and not human, and (4) are sexual predators who prey upon human females.
They then make an unfounded assumption about how some people will react to this fictional species:
To some readers, kleptons will come across as a racist metaphor for Black people.
They then moderate the indirect accusation, while still placing the onus of the accusation and also how other people will react onto the OP:
I am sure this was not your intention at all, but part of writing means being aware of how your readers may interpret your work.
They then delve into human history a bit, which is not relevant to the question at all:
Historically, white supremacists have depicted Black people as (1) a biologically distinct race who (2) cannot or should not coexist with white people, (3) can reproduce sexually with white people but the offspring are considered to be black and not considered to be white, and (4) well, hopefully you get the point.
They then moderate the indirect accusation again:
I'm going to assume this is absolutely not how you want your work to be interpreted
Yet continue to press the indirect accusation by rationalising the unfounded assumption that unnamed other people will react in a certain way. And more than that, inflates the indirect accusation by bringing in a variety of socially fringe elements and making yet another baseless assumption about how people will react:
but the point I'm making is that what you're describing could reasonably be interpreted this way. Racists could read your work and think you are on their side; Black people could read your work and be reminded of harmful depictions of themselves. To avoid this, I think the rest of your world needs to be carefully built and your story carefully written.
First, I should note that as of this revision, the question itself has gained +9/-1 votes and that all the answers apart from one have gained anywhere from +3 to +21 votes. Kaya3's answer has gained +3/-3.
I'd interpret this as a modestly well received query and a variety of reasonable answers with no indication in comments or voting patterns that anyone other than Kaya3 believes there is any inherent racism in the fictional race described.
I'd argue that this is an individual / personal opinion about the question's matter; and also that it does represent a valid concern in general though not in specific.
Having scrutinised the original question again, I still can not find any hint of racism or any other -ism in the text of the question. Nor can I find any "parallel" with the historical notes provided. I still maintain that this is essentially the Amazon Question: a single sex / gender population that needs to reproduce, how can they do this without needlessly antagonising their reproductive receptacles.
Far from the claim & accusation of racism, the species in question categorically negates accusations #2 and #4: they explicitly wish to coexist peacefully with humans, and they are, by nature, not sexually predatory in any way.
A sexual predator is a person with a deviant sexual urge.
On the matter of the historical notes: it is not "white supremacists" who determined that Africans are a biologically distinct race. Ordinary scientists & natural philosophers came up with these and other similarly bizarre propositions about different ethnicities of humans. The ideas that blacks shouldn't mix with whites or that their offspring are considered "black" rather than "white" are unscientific conclusions. None of these historical notes correspond to anything specified in the question.
There are several issues going on here that we should consider.
Banner Question: To answer your banner question, Should we warn about (presumably unintended) parallels with racist tropes? I think the answer is clearly and obviously YES! We should warn an OP when a question contains racist content. And in fact, WB.SE practice has been to do just this. Not just racism per se, but with any kind of obviously discriminatory or defamatory content.
Underlying Issue: The issue being addressed here is not one of what should be done, but rather how we should approach it. I'd argue that we already have a reasonable process for addressing issues of this kind:
- Ask for clarity -- if you think the question has questionable contents, just write a comment asking the OP for clarity! "I think X, Y and Z could be interpreted as racism / anti-religion / discrimination; can you please clarify?"
- Flag the question -- either flag it for closure and give a reason, or flag it for moderator review
- Start a meta discussion -- If the OP doesn't respond or if you really still think there is a problem, bring it here so the query and claims can be evaluated.
- The usual reactions -- downvote and give a succinct rationale -- "I'm downvoting because I think your question is racist and you haven't addressed this concern."
Moderator Intervention: It's my opinion that while I believe your intention was noble enough, as you explain in your apologia above, I think you didn't execute very well. A moderator is kind of limited in what actions they can take when a query or a response is flagged for attention. A mod can choose to ignore the flag, they can modify the post or they can delete the post.
The choice to modify a flagged post is, in my opinion, almost always the best choice. In this case, a prudential judgement was made to preserve the part of your response that does actually try to answer the question, while also respecting the concerns of whoever flagged your answer. He redacted that part of your answer that, in his moderatorial judgement, does not actually address the question, but rather addresses a particular concern of yours.