You missed the reason that payment processers set these terms. It is not because they want to.
It is because there is a minority who think sex is dirty and only should be done in the family and they will take anyone who is even slightly helping sex workers to court. The only protection public companies would have is there was a law stopping these court actions but no lawmaker is going to do this as the same minority would attack them and the majority would see the company as helping sleaze and what that minority see as sin.
Note that any new payment processor would be hit in the same way.
The issue is that a minority can persuade the majority of things even if they are untrue or destructive.
It is because there is a minority who think sex is dirty and only should be done in the family and they will take anyone who is even slightly helping sex workers to court. The only protection public companies would have is there was a law stopping these court actions but no lawmaker is going to do this as the same minority would attack them and the majority would see the company as helping sleaze and what that minority see as sin.
Note that any new payment processor would be hit in the same way.
The issue is that a minority can persuade the majority of things even if they are untrue or destructive.