If you've ever run an actual platform, you know that the idea of "everyone should be free to speak whatever they want, no matter how wrong or ridiculous" is not nor has it ever been true, in the case of private platforms. Platforms everywhere ban people who call for active and immediate harm to others. Platforms everywhere ban people who spam those platforms with unpaid for ads or phishing. Platforms everywhere ban posters for putting up literal random garbage (as in literally random ascii text). This isn't controversial, but it also isn't "allowing everyone ... to speak whatever they want". Now having said all that, if we look at platforms banning Covid misinformation, I ask you:
What is the fundamental difference? This isn't the government excluding someone or suppressing speech; this is a group of individuals A deciding that they don't want some other individuals B to say the dumb shit their saying on A's platform, leading A to ban B.
A normal response based on reality to this situation is to say things like "wow, fuck group A" or "wow, fuck group B". Even saying "but I like group A, they're in the right!" or "but I like group B and I think we should listen to what they have to say!" All of those are pretty normal, and sure, say what you want. But saying "truly this is the fall of what once was beautiful and good" is being more than a little dramatic.
Like I said, say what you want. But I disagree that some "fundamental shift is happening" here.