I feel this rises to the level violation of fundamental human rights at this point, and there's nothing to be done about it.
Honestly it really IS a human rights violation in a much more real way than a lot of crap. Many people sperg (in my opinion) about human rights violations which are relatively minor in comparison, but actively being DENIED a payment processor is effectively denying several other rights by proxy.
As for arguing it, shit, idk. Argument wise I suppose you could say the inability to use funds essentially restricts other human rights like freedom of speech, travel, right to food, or whatever, but as for someone LISTENING, that might be another issue.
I find it weird, SEIZING a bank account has all kinds of restrictions, rules, ect, a govt (supposedly) shouldn't be able to just fucking SEIZE it. But if a processor friezes it (kinda a psudo seize??) by refusing it, its fine despite being the same result which IS illegal. Really it SHOULD be a violation since even the most basic logic jumps show it as such, but I don't think it would work unless you took it to court somehow. I mean money like it or not is a necessary vehicle for so much and so if you have a RIGHT, but that right costs money, but the processor refuses to let you USE that money, thats a human rights violation, and I think its pretty clear.
Going to court with a payment processor sounds FUCKING AWFUL, but especially if you could make good examples of things you INTENDED to do with the money which are ENSHRINED rights which are not to be restricted in the united states, but were, in essence, restricted due to this, I wonder if you would have a case?
The logic isn't entirely off from what I've heard of in some case law, since if something is expressly illegal and you just do the illegal shit with extra steps, and its clear, it should (in theory) be treated the same (discrimination on sex and other characteristics has been treated like that historically, IE "we don't discriminate against women, you just have to carry x weight", is still legally seen as discriminating against women in many places). Then the issue is just finding a solid case of a thing you were trying to do, which you were PREVENTED from doing, which it would be illegal for a company to prevent you from doing via OTHER means. Maybe im a bit too stupid to know what this would be, I'm guessing its not food since you clearly love your cheese but, its a thought?
Maybe all my thinking is total dog shit here, but im trying.
And heres a really really retarded thought but....Kiwi religion?..... Religion IS a protected class, that coveted, special, wonderful thing which supposedly is immune to stuff like these kinda stuff if its "targeting a religion". If you made a religion about your forum and could basically imbued your forums and charities goals into a recognized religion, this COULD function as a bulwark against that, since then it would be discrimination against your religion. Sounds weird but, its a thought.
Forgive me if literally everything I said is stupid, I feel like I'm throwing shit at a wall hoping something sticks.