> If I were to threaten to shoot your kids if you again post something that I don't like, while making clear that I know where you live, my speech will certainly impede with your ability to express yourself freely, or wouldn't it?

You're right, certain speech, like direct threats of violence can impede on other people's right to freedom of speech. But such speech is illegal even in the US and also banned on Kiwi Farms.

How about coordinating to targeted attacks? Imagine a muslim terrorist groups forum and how their coordination works there.

Is it legitimate to take that platform down? You don't have to answer, the US certainly thought so during the past wars.

Is it legitimate speech to write some vague SMS to the wrong person? You don't have to answer, whole wedding societies have been killed for that speech.

Now one could argue, "Yeah but they might have been terrorists, or associated themselves with the wrong people."

But what is terrorism and why does a free society break it's promise of freedom of speech to fight it? Terrorism is trying to reach political goals by (often) violent means, with the aim to create fear. This fear stifles the free discourse in a free society by targeting specific symbolic targets. And isn't that a definition that fits many fringe political groups that would target individuals and make their lives hell like it apparently happened in the case of KF?