There are two recent questions (one and two) that ask for the existence of an anime (or manga) that satisfies certain conditions. They are not list questions; rather, they are clear, and probably also focused and answerable (I will get to this later), questions about anime/manga, so many, but not all, people agreed that they should be on-topic here.
If we happen to know of any anime/manga that satisfies the requirements set by the OP, then it is job done. But what about the case that no one is able to identify any such anime/manga? Can we say "no, there is no anime/manga satisfying those conditions?" It is clear that, in this case, the question is not reasonably scoped because no one can ever see all the anime and manga that are out there, and therefore no one is qualified to verify the truth of the claim. Then one question follows another: how do we determine whether questions of this kind are reasonably scoped or not?
I investigated the status of this kind of questions on Sci-Fi SE, and it seems that they are closed as not constructive there (e.g. questions one and two). Should we do that, too? And if we want to allow existential questions, what should we tag them with? The two questions on Anime & Manga that I mentioned before were tagged as identification-request, but are changed to anime-history to divert the flow to an already over-saturated tag. However, I feel that both these tags don't adequately describe the nature of those questions well, and we certainly don't want to pollute the anime-history tag. How should we tag them?