Pretty sure they were banned for taking on a public political stance supporting disinformation peddlers like Alex Jones. Payment processers don't want to be associated with this kind of content for obvious reasons.
Why don't payment processors want to be associated with someone calling for violence in the streets while peddling conspiracy theories they know to be untrue?
They don't want to become liable for any illegal behavior and end up having to pay a fine.
They don't want to be associated with any political stance that might not agree with the vast majority of the population because they want to have as many clients as possible.
Is/was it the platform maintainers applying their own morals, or is it the money (advertisers) who don't want to be associated with these topics?
The walled gardens are already quite ridiculous, with FB censoring Michaelangelo's David and the Napalm Girl, giving us a kindergarten version of the Internet (although funnily enough, they can't censor fake news, so the "children"'s minds got brainwashed there).
OK, how about this: he's a polarizing nutcase who has adopted controversial and unsupportable standings on several calamitous events in the past two decades.
Most people that see a mainstream business supporting him assume that business adopts those same ideas, rightly or wrongly. So, the perception of supporting Alex Jones can be incredibly damaging to the reputation of a business.
I m sure paypal or patreon are doing business with many criminals or even terrorists who are unknown. The reason is the bad PR and negative publicity they get from these channels.