It's the principle that when your speech is on-message, you're counted in our number, whereas when your speech is off-message, you've been brainwashed, therefor

It's the principle that when your speech is on-message, you're counted in our number, whereas when your speech is off-message, you've been brainwashed, therefore you're also counted in our number, but we are also going to shut you up by any means necessary. The sophistry and belligerent obtuseness is insulting. This is a signature tactic of the "safe space" crowd, and people tend to (quite understandably) grow allergic to it. Don't take my word for it: watch a couple of videos of verbal clashes between these goons and people who don't agree with them, and make up your own mind.