"prohibits adult games"?
Is that really it cuzzzz there's a lot of adult games on itch....
And yes one's you can purchase.
So I don't think it has to do with it being "Adult" content.
I suspect it's more likely some of the specific type of content that's in the game which is seen very negatively by many platforms.
Not saying I have anything wrong with the content. As I wouldn't be here if I didn't enjoy it. Just seems like if itch were to prohibit adult games being sold. I think 20% of it's library would vanish.