Some entities care. Especially in the English speaking countries. They do outlaw even cartoon stuff. It is of course laughable, but they also have their obscenity laws that are equally idiotic. There are states in the US where sex toys are illegal. No factual discussion is possible with people that promote such bigotism.
I believe they try to invoke some slippery slope fallacies about morals and and whatnot. Ulimately saying that playing games where you can kill people will make you kill people in real life. Oh wait, that one was disproven countless times. I meant they want to ban sex games, so peopl will not rape and abuse. Hmm. Yeah, that argument will work, since it worked for the violence so well.
Anyways, the problem is entities like patreon, that have their own agenda and push it with their market weight around. They are unpredictable and hypocritical. They want their share of the adult cake, but instead of banning only the actual illegal stuff, like actual abuse, they give you trouble if you do not go out of your way to make clear that the fictional pixels are of legal age. And unrelated by blood.