I know this is not going to be a popular opinion, but they're right that saying "I'm going to rape that bitch" is not a crime. Nor should it be. If it were, imagine how many people would have been arrested by now for posting hateful things about politicians on Facebook. Now, obviously this isn't a nice thing to do, and if you actually send threats to her personally somehow, you should be charged with harassment.
But going on reddit and reading through a subgroup dedicated to people who disagree with you, and being shocked to see threatening messages or language, is a bit over the top, in my opinion.
They were killed by words?? I'm pretty sure they were killed by actual physical people wielding guns. Now you could try and argue that, had hate speech been illegal it would never have come to that, but suppressing people's opinion and forcing them to keep it to themselves is rarely helpful in that way.