Knee-jerk off

I just coined a new term [note: Google tells me others have used it] for that kind of person who doesn’t wait until they even know what something is to start putting it down unintelligently and counterfactually: a “knee-jerk-off”.

I have a target person in mind and yet I’m too genteel to name them. They are hardly alone, though. This class of people exists, and they can hardly wait for a new concept to arrive so they can lay into it. If and when their doomsaying proves wrong, they encyst and wait for another thing to decry. Seems like kind of a pissy way to live a life to me.