But yes, a court marshal is a completely different matter. You're speech is restricted if you take steps to work for the government in any capacity. As is your legal channels.
"Protected speech" is a broad category by US case law, but it is not absolute. Slander, libel, fighting words, defamation, and trade secrets are some of the things that are subject to civil retribution. "Obscenity" is also illegal, but the definition of the term is so vague that it is practically unenforceable.
As for “the other way around” - what I saw the right wing complaining about was “being canceled”. Freedom of speech has never meant freedom from consequences for your actions. A private business is well within their rights to fire you if you’re posting racist or homophonic slurs online.
The only thing the first amendment provides is freedom from the government impeding your speech. Doing things like, you know, threatening jail time for journalists who say things they don’t like. Or, in a functioning US government, pulling funding from colleges because they’ve got students protesting over the current situation in the Middle East.
Just saying that it might not be the best model.