anne O'nymous not saying you're wrong but what
ClockworkGnome is saying sounds pretty believable.
I didn't said that payment processors aren't the problem, but that OnlyFans case and Nopy one aren't at all related.
The problem that OnlyFans had to face is the result of some lobbying who use prostitution rings as excuse to push their puritan agenda. It's not new, and it's effectively what led to Patreon bans over some adult content.
I can't find the link, but I posted it once, few years ago. It's a English ex-politician who started a lobbying campaign to put pressure on Visa and MasterCard because some of the adult account on Patreon was used for prostitution. He then discovered that there were fictional bestiality, rape and incest, and added this to its complain.
The said payment processors didn't really had options here. Either they took action, asking Patreon to clean up its content, or they were taking the risk to face a campaign of discrediting claiming that they were supporting prostitution, incest and rape. This in the same way that MasterCard didn't really had options when they were facing the same risk, once again regarding prostitution.
But, while they are a weapon by destination, not the effective cause of the problems. Visa and MasterCard can't afford to loose the market in favor of PayPal, while PayPal itself can't afford to loose its dominant position in favor of the many competitor ready to take all compromise with the lobbyist in order to take the first place. And this, the few puritan lobbies understood it and clearly abuse of it.
But the problem that Nopy is facing is different. Mostly it's due to the fact that it wasn't a society, and therefore was less sensible to pressure.
Hosting sites are a threats for many industries, since it's the main node of any piracy model. When they are a society, those industry can put pressure on them ; comply to our request, prove that you are worthy, else be ready for troubles, we can destroy your business model. But when they are a purely independent entity, relying on donation to exist, like Nopy was, there's no way to put pressure on you. At least, no way others that justice, but you need proof that they did something illegal to play this card. If you loose your trial you'll face a really bad press, especially nowadays and if it was against an independent structure ; in fact, the risk exist the instant you start the law suit.
Therefore, the pressure was put on the payment processors. It's just an example, but lets say that a society like Disney phone to Visa CEO and say that, if they don't stop to deal with Nopy, well, starting now they'll use MasterCard service instead, you comply... It's absolutely not legal, but you can't prove it, as well as you can't afford to loose all the benefits you make thanks to Disney.
It's purely theoretical, there's no proof of all this. But the fact is that all of them put Nopy in a position where they can't solve the issue. There were no possibility to negotiate a compromise, and no real reason was gave to explain their position. This is not the usual behavior of payment processors, mainly because it's not legal to unilaterally stop a contract this way when you're a society ; they have to explain what is the problem and present conditions (possibly impossible) to avoid the end of the contract.
The fact that they didn't is the proof that they aren't at ease with their position. And it's not due to the pornographic content hosted by Nopy. They don't care this much about pornography, it pay well, even for them, and any partner involved in it have to make a blocked security deposit for tenths millions US dollars in order to be accepted ; this in order to cover the risk of fraud, that is the only thing that payment processors fear when it come to adult content, since it's very high with this topic.