Payment processings are monopolies. More precisely, oligopolies. See how easily Mastercard and Visa drop PornHub payments after the news paper article. It's not a court order or even a trial. There is mainly zero way of doing business without fully government controlled banking entry-points.

Yes, there are cryptocurrencies available, so if we can fully legalize it and promise that we don't touch anyone's private transactions (as well as businesses officially accepting crypto) - that would be an argument.

For better understanding how bad it is: it's non trivial to even accept worldwide payments for small business/individual in the internet if you are, say, from Ukraine, Russia, China or lots of other countries not processed by stripe/paypal for some political or legal reasons. Apart from that, there is a "free" market of two payment processors in the internet and two card processors =)