I am genuinly interested about your opinion on Steam. They have adult games. Infact they do host games, that were "targeted" on Itch.
Also, what about Patreon. Many have that too, especially, if they are too small or unfinished for Steam.
Maybe Gamejolt is more to your liking. They purged the pixel nudes - and lot's of games that were actually sfw as well, as is the way with purges.
I for one would welcome a split in a kid-friendly itch and a mature-friendly itch. That might also get rid of all those disgusting "horror" games. Especially the English speaking countries equate mature with nude pixels. But violence and scary stuff is not kid-friendly. It is for mature audience.
But till then, (de)activating the content in search and browse has to do (wich sadly does not filter out the horror games).
Oh, and promoting games is discouraged for all games, not just nsfw. If you see threads with promotion, no one bothered to complain about them, it does not mean they are allowed. And with less than 100 page views a thread, why bother. But it is specificallly forbidden for adult games in the one place where you do can promote your game in public forum, the announcements. Understandable, as you have to put screenshots in those threads.