Measuring and ranking systems like this always involves impossibly circular problems. Ability differs between populations. The best system will produce the best possible result for a population, not necessarily the best overall result.
The law is clear on what constitutes illegal speech in the US(1). ISIS propaganda, to the extent it incites violence, is clearly illegal. If The Daily Stormer had engaged in speech that incited violence, they would have been shut down and imprisoned. This story is about legal but unpopular speech and if something is legal to say whether it should be allowed to be said. (And the role of large corporations effectively acting as gateways.)
The various implementations of Marxist ideology have resulted in a far greater body count than Nazi or Fascist ideology (1) yet erstwhile young people (and their grizzly tutors) freely speak of implementing Communism and sport Communist regalia in public. By your measure, we have even more reason to no-platform such people and deprive them of their rights to speak and assemble
>These people do not respect free speech. They do not respect freedom. They wish to destroy all of these things and they are entirely upfront about it.
This is an ahistorical claim. The censorship laws of the German Federal Republic (1) were first imposed by the Allies during occupation and were only relaxed, in part, after the official end of the war in 1949 (2). Germany was not a fully sovereign state until 1991 (3). Implying that these laws were the result of the population deciding to impose them upon themselves after "learning" a "lesson" is, in fact, the inverse of what actually happened in that they were intended to teach the Germans a lesson as part of their subjugation.