do not blame too much the payment processors
their actions were started by a letter from a gaggle of authoritarian pearl clutchers called "Collective Shout" based in Australia
https://www.collectiveshout.org/our_team
https://www.collectiveshout.org/open-letter-to-payment-processors
so the payment processors pmuch responded the way they did because "oh shit the optics" and the worry of whether they could be held responsible over people accessing illegal content, as apparently one was clobbered over the head because a kid bought access to a porn site or something
No, absolutely blame the payment processors. You think these clowns are the first to write them about it? They (the pps) even tried to force only fans to ban porn a while back, but for whatever reason backed of in the end (somebody probably had a second look and saw how much they really were making in fees there).
You can also still by all kinds of nsfw stuff with your card, so it definitely aren't the optics they care about. Christ, nobody even considered Visa etc. to have an image before this, they were just an unobtrusive middleman.