The government has been shutting down death threats and open sedition since the birth of the United States. There's a difference between free speech and saying "i'm going to go down to the capitol and put _______ head on a spike" . That's not free speech that's a threat. "Let's blow up ____________" is also a threat and not free speech. Also facebook, twitter, etc should not host such things, and they decided not to, thus this really isn't about free speech in the Constitution and no one really has ever had a right to post such things anywhere unless they have a contract that says it, and such a contract would be illegal anyway. The government didn't force AWS to remove Parler.