Somehow it's always a concern that governments might abuse hate speech laws to "silence dissenting ideas, unpopular speakers, and disempowered groups," but it's never a concern that the purpose of hate speech is to do exactly that.
I don't know what they're teaching kids in history classes these days, but it isn't history.
Well, no. The people have guns too, at least in the US - the extremists certainly do as the recent trend of mass shootings can attest, and the words of extremists are intended to lead to violent action, not simply be debated on internet forums and turned into memes. And the government has speech.
At best you could argue that the defense of absolute free speech is implicitly a defense of extremism and of extremist violence as a necessary lesser evil compared to censorship in any form. A similar argument is sometimes made regarding mass shootings when defending the Second Amendment - that popular gun violence is a price Americans should be willing (even grateful) to pay for the liberty guns theoretically provide. If so, that's an argument I don't necessarily agree with, in either case.
That's what I tell myself, anyway.
Yep, these ideas were as controversial in the day of Socrates as they were in the day of Voltaire and, for that matter, Barry Goldwater ("Extremism in the defense of liberty is no vice.")
So: no, to answer gamegod's original question, the argument is not going to "die now." S/he is hardly the first or the last to try to wish it away, but that's not going to happen.