I feel like this post doesn't address the real risk that comes with suppression. What if we lived in a very different society, where basic ethical views were far outside prevailing norms? Is there a case for choosing discrimination as the newly banned form of speech other than the fact that egalitarianism is a key value in our society today--what is it?

I don't know much about Parler - it sounds like the key people there were real assholes and possibly criminals. There are any number of reasons that might apply for getting rid of it. Parler might not be the limiting case that decides our rule.