If ypu ban nazi speech as the one major caveat to free speech, then they will never be able to exist in large enough numbers that you HAVE to fight them.

That's deluded speculation & the old antifascists knew that.

I remember other instances of unexpected support, too. There were times when, during speeches I gave about the Skokie case, Holocaust survivors courageously stood up to say that I was right to have represented the Nazis. Several years later, another survivor sent me a letter saying the same thing. These survivors said that they did not want the Nazis driven underground by speech-repressive laws or court injunctions. They explained that they wanted to be able to see their enemies in plain sight so they would know who they were.

It just drives fascists underground & not by much: the German AfD aren't struggling. Better to see them right where they are.

Such legal restrictions are trash. Are we going to ignore their nonspeculative harm mentioned before when such restrictions already denied the Jewish War Veterans a permit to march in Skokie? Look how they work for Germany: live police suppressing pro-Palestinian protests as anti-semitic, raids & arrests over calling a politician pimmel, internet patrols penalizing vitriol, insults, & satirical images of politicians showing fake quotes. Look how they work for UK: designate Palestine Action as a terrorist organization, arrest pro-Palestinian protesters, arrest someone over a social media post backing Palestine Action.

Your claim is a reach: it's arguing for a doubtful benefit at the cost of a clear, definite harm to democratic society that really serves a fascist agenda.

Its the logical conclusion of the paradox of tolerance.

It's a paradox without a single logical conclusion, and you likely misunderstood it.

[^popper-source]: Source: The Open Society and Its Enemies, Karl R. Popper