It’s like NSFW or even more relevant NSFL (also spoiles) - perfectly fine for some recipients but not for all, so best to LABEL IT. Labeling is compassion.

Then again, people who post AI slop against the wishes of the recipient communities tend not to be the most conscientious?

A relevant rule #1, above even the one about NSFW and another one about spam:

AI Art: While we appreciate AI generated art, there are more appropriate communities to post that type of art to. Please keep posts to non-AI generated art only. This rule includes AI art that was then manually manipulated (e.g. drawing on top of something generated by AI).

That reads pretty clear to me?