Oh, you're so close. The fascists are parasites: they only tolerate liberalism insofar as it allows them to spread their ideas. They desperately want to--and will--silence their opponents as soon as they wield power. They view tolerance as a weakness, and the social contract as a game to be played only until it can be rewritten.

I do not dispute that Nazis can, legally, say what they say. I don't even necessarily think it's bad that their speech is protected. But their speech should have consequences, and platform owners can and should tell them to fuck off.