Apparently it's an organisation called "Collective Shout" which has some deep influence on the payment processors. Don't ask me how exactly that works out, but that seems to be the case.
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I do however want to clarify that I dont agree with either solution. Censorship online is a dangerously slippery slope which could cause the destruction of the internet as a whole. I'm only saying that if I had to choose, it would be the lesser of the 2 evils, rather than nuking every single adult game on the market across all platforms. Steam an itch got hit HARD because of these changes and I doubt it'll stop there. This issue is much bigger than just losing our perfectly legal adult games. We have a rough ride ahead of us.