Governments often try that kind of nonsense. Usually against organized crime, terrorism, child abuse.
But in the end it’s just used for the heavy crimes like copyright infringement
1st - gag orders issued by secret courts, no trial, no apeal, can't even talk about it (can't even talk about the gag orders themselves, basically a gag order on a gag order). We only found out about it because Yahoo (out of all of them, the least you'd think would fight this) briefly tried to fight it. All the top CEOs got them. Yahoo briefly tried to fight it at some point and some court docs got out, but it wasn't much.
4th - multiple cases of confiscating cash without a trial, probable cause or anything of the sort. It's called "civil forfeiture", it's been done at both state and federal level, and it's so insanely full of mental gymnastics that at some point they tried to argue in court that "the person is not suspected of anything, the money is suspected of a crime". Bananas.
5th - there's a case where an executive was caught up in some investigation, and she was being held in contempt (jailed) over not divulging an encryption password. I haven't checked on the case in a while, but the idea of holding someone in contempt for so long defeats the purpose, and the idea of having to divulge passwords vs. having to provide a safe combination was apparently lost on the courts.
The lesson is: stay active, stay vocal, stay in the media, and prepare for a very long haul. And file lots of lawsuits challenging everything!