So is the great firewall of China.
Russia chills speech with assassinations.
Nearly all your examples are proving the opposite of your point.
The point is that merely thinking saying free speech should be free is not enough. As you well illustrate, the debate on what exactly free speech is means we need to define what falls outside of it very clearly.
This is ahistorical. The only "censorship," they faced before they were granted power were in response to an attempted coup. They were radicalized prior to any censorship.
There's just something that doesn't sit right with me about indicating that censorship lead to a radicalization of Nazis. Violent anti-Semitism has eternally been a problem in Europe and both Austrian and German nationalist parties were entrenched in such conspiracy. It was always a violent movement.
Free speech won't and doesn't survive contact with the human race without an effective defence, and history shows merely counting on people to use more free speech leaves free speech and democracy open to coordinated brute force attacks.