even steam could not fight back why you think itch can? Anyways both steam and itch can cave in for a bit and behind close doors be making plans to fight this.
Valve couldn't fight back because of the exact games being targeted on Steam - they were nsfw games with very specific themes. Fighting that would have been social suicide, which the payment processors (And the cults that own them) knew, which is why that one was much more targeted.
Valve might be able to fight back against a total nsfw ban. But we shouldn't rely on that, because they might just look out for their own bottom lines instead.
People need to fight back against puritanical cults and force the government to hold billionaires accountable. We can't expect capitalism to fix anything, only be happy when it sometimes does.