Freedom of speech is not about hearing the ideas you like but the ones you dislike.
That is, if you claim censoring ISIS speech is okay but not Parler speech, then you must also be claiming that there is a line somewhere between the two that is being crossed. You are therefore acknowledging a limit to free speech. But that isn't the point yet.
The point is that you (not necessary you) are drawing a line at all. It's that there is a line. And if there exists a limit to free speech, it means someone has to decide where that limit is placed. We are almost to the point.
And if someone gets to decide where the limit to free speech is placed, who gets to make that decision and why? Clearly you have put that line between ISIS and Parler according to your own belief system (or maybe not, you haven't explicitly denoted anything). But the point is that there exists a reason to limit free speech. I promise the point is coming.
If there exists reasons to limit free speech then we have a problem. You see, you and I may agree ISIS should be de-platformed, but other people may believe other things and therefore have other reasons. The point is that there is no such thing as "free speech". That everyone has their reasons. And that the people shouting "free speech" often mean "free speech within the thresholds that I am comfortable". That nobody actually, truly, deep-down believes in "free speech".
The point is that "free speech" is a myth.
So quit wasting your time calling out Amazon for infringing on something that doesn't exist (again, not necessarily you).
Big tech made a decision that the hell with the judicial system, Democrats now have the executive and the senate, we have to bend the knee and kiss the ring to keep our section 230 and don't get taxed into oblivion.
If I dont have to wait for a child porn conviction to ban you from my site for posting 'illegal' content. I will do it immediately and sever all contracts.
Its funny how we have the freedom of association right up to the moment it affects those supporting fascism, then all of a sudden a different set of laws matter.