I've been particularly mad about payment processors doing this shit for ages now and nobody really listened until it finally happened.
A while back, Toffer Team did a crowdfunding campaing for their Lip Lewd Idol visual novel series. They racked up 23k and PayPal froze the account and stole all their crowdfunding money.
I said even back then that this kind of behavior was an attempt to normalize censorship and now its happening. I'm just as furious about whats happening as you are, if not more so.
Visa and Mastercard are a duopoly that actively collude with eachother and I can't for the life of me understand why they havent been forcefully broken up by the government.
I'm not american, but if you are, contact your representatives. Theres a bill in the US right now being worked on specifically to make it illegal for Visa and Mastercard to decide what you do with your money.