You mentioned the word outcry in your first post. I therefore assume we are not discussing legality but the response of the US public. Which is not as much as you believe it should be.

The explanation is that the American public does not actually care for free speech as a human right that much. Your own dismissal of corporate censorship as not 'actual' censorship reinforces my point. It being illegal on it's own won't necessarily cause an outcry.

Especially when it's done to people that the American public has been propagandized to hate for decades. Ivory tower scientists, 'working' for the government like a commie instead of working for a corporation, like Tesla.