Honestly, I think most people just don’t really care that much. It’s kind of a niche for a specific audience, and if these games keep getting made, it’s because someone is supporting them. The internet is a place where even the weirdest and most extreme fantasies find their crowd. That doesn’t mean “everyone thinks this way,” it’s just that the most shocking stuff gets more attention.
Plus, 18+ topics are awkward to talk about, so people don’t really want to argue publicly. Some are afraid of backlash, others just say “it’s fantasy, chill.”