Thats what censorship boils down to and why it doesnt work. The answer to your initial question is being able to communicate why something doesnt work. Which apparently i am to stupid to in this case. But thats a stupidity people can work on, while censorship has fundamental issues.

edit: was an answer to the first sentence before the edit

To the rest, the problem is finding a basis solid enough for authoritarian action on such a delicate problem as speech (which requires another level then say a court case). Its not either quicksand or a rock but a minimum required level on the spectrum. If you dictate facts, you are dictating that this description encompasses all perspectives and every additional one is wrong. More then that, you dictate that those are all the implications. Its claiming you reached the end of knowledge.

You either can convince people that you are talking about facts or you cant. The problem is communication and not lack of force. As the issue here is only solvable with the former without accepting an inevitable crash in the future. You bringing up censorship is counterproductive for this reason. Somebody (not necessarily me) being able to explain that should be an example for an alternative.

Should have had a coffee first sorry