I am not at all troubled by the immediacy of this shutdown, I am much more troubled that such threats have been allowed to continue for decades.
For example the gun culture. I would like to see the same immediacy that ended Parler applied to the Second Amendment, a constitutional right for unstable and deranged people to own massacre weapons. With mass shootings so common they scarcely make the news anymore, it would be great if we could read the clear writing on the wall and decide that the time for individual arsenals is over and get rid of them.
But we can't.
Same for global broiling; we are standing on the tracks and watching the train headed straight at us yet debating the proper balance between economy and survival.
Sorry, but being able to shut down a site that promotes political violence doesn't trouble me in the least, but then I'm not a free speech absolutist.
And, frankly, I find "who gets to decide" arguments to be contemptible, weak, and ultimately inadmissible. Too many debates are shut down because someone points out the potential for subjectivity, as if coming up with reasonable criteria is an insurmountable challenge.
I signed up for Parler just to see what it was about and mostly saw a lot of people with big mouths the great majority of whom are probably isolated, miserable, and ineffectual. But the few who will act out their paranoia are going to kill a lot of people.
Shut them all down.