Is this a violation of the 1st Amendment or a way to skirt around it?
The question to ask is whether any of these accounts would have been allowed if reported by people. There’s no evidence that the FBI was making threats that something otherwise allowed had to be removed.
The cop was telling the bouncer, "Throw that guy out."
And the bar owner did what the cop said, because the police department had threatened to shut down bar owners in the city for the last three years.
A bar owner that does not follow the instructions of the authorities is going to find their bar closed in short order because they have to comply with the law and with instructions by parties authorized to give them.
To paraphrase the trope that those that don't like Twitter are free to create their own: if you don't like the way society works then you are free to create your own. On Mars or something.