It's not the same thing. A constitutional court has independent judges bound only by their conscience, the constitution, and precedent, the government is answer

It's not the same thing. A constitutional court has independent judges bound only by their conscience, the constitution, and precedent, the government is answerable to its voters. And if you actually get to a point where all these checks and balances do break down, you have much bigger worries than just suppression of speech (which at this point becomes just a further symptom of an autocratic or totalitarian regime, not its cause).