Free speech is prevented by the use of force. We held an election. The results where not what some people liked. They tried to cancel the people's voice. That is the real speech suppression here.
The principle of free speech is the idea that open discussion and debate is sufficient to resolve conflicts of ideas. Using force to end discussion is not free expression.
Of course there are limitations when fraud, slander, threats, and the like. But those should be considered in trials by peers or judges as decided in a fair court with due process. Again, words, ideas, and fair institutions are the rule, not decisions by the involved parties who happen to have enough power to get their way.
At least that's the principle.
Should the broadcaster cut him off? I say YES!
In those cases, you make the best argument possible to refute that drinking bleach us harmful... which honestly isn't that hard to make. The hard part is building up a reputation as being someone respectable and respectful enough to deserve attention. I think that silencing of sincerely held beliefs undermines efforts to actually persuade, inform, and make progress (and peace!).
Absolutely. However, not all speech is protected speech. At least not in the US.
Speech can also be part of a conspiracy. And conspiracy to commit criminal acts is a felony.
Which is, as I understand it, what the issue is in this case. Apparently (if you take Amazon's word for it, and once the dump from Parler is available, we can see for ourselves if that's true), folks on Parler were planning acts of violence and insurrection on Parler.
Again, that's my understanding. And if that is the case, it's not just folks exercising free speech. It's folks planning violence and insurrection against the US government. Those are absolutely crimes and not protected speech in the US.
N.B.: IANAL
Greenwald specifically claims that this is a lie.