[stcredzero]

There is a pretty direct line drawn between speech and violence against out-groups; anyone who says otherwise would do well to read about the Rwandan genocide and their 200 days of public radio broadcasting demonizing the Tutsis prior to the genocide itself.

If you're concerned about the "pretty direct line drawn between speech and violence against out-groups" then you should be paying keen attention to the normalization of political intimidation and violence in the past several years.

https://www.youtube.com/watch?v=aC4u1zo6OpQ

The fact that the media have been giving groups tacit support, by not or minimally covering their assaults and vandalism, while even giving them positive spin, should raise some concern.

I haven't often seen the position that incitements to violence should also be protected speech

They should not be. "Punch a Nazi" -- despite the vileness of the purported targets -- shouldn't be allowed. "Milkshaking" is incitement to assault. The fact that Twitter allows those to continue shows a groupthink bias at operation there.