For consideration: Stormfront exists solely to incite neo-Nazis to violence, and its members have murdered almost 100 people (pre-2014, that number is likely higher now)[1]. I wouldn't be shocked or constitutionally worried by a criminal case against them.

When you consider that Gab is really just Web 2.0 Stormfront with extra dogwhistles ("free speech" instead of "murder the Jews/Muslims"), it's not all that surprising that criminal charges are floated.

[1]: https://en.wikipedia.org/wiki/Stormfront_(website)