"Do you not accept a line where free speech threatening violence harms other free individuals? "
I don't.
I rather have people saying out loud, that they want to kill me, than saying it it in private and then just doing it ... so I - and others (like police) know whats going on, and can prepare for them.
If you forbid things to be said out loud, they will just boil hiddenly, until they explode.
Do you not accept a line where free speech threatening violence harms other free individuals? This isn't a thought excercise, the Daily Stormer is a group calling for the extermination of people based on race and religion.