The payment processors interpret the networks’ rules, you do understand that right? If they’re banning something, it’s because the networks either outright are banning it too or have put enough restrictions and constraints in place that the liability for the transaction doesn’t make sense.

The payment processors are doing what the networks tell them to do.

It’s not like the processors are actively looking for ways to turn down money; they want as many transactions going through them so they can earn their share of it.

The entire US financial apparatus is part of the problem.

There were several efforts to restrict the people’s right ability to marshal resistance to tyranny and Visa/MC was very much involved with that even though they were not the only ones.