Well, it's occasionally hard to see clear evidence that earth (or, specifically, tolerable conditions for human life on it) is rapidly heading towards the shitter - and there are plenty of people who'd rather go ad hominem than engage with the scientific evidence of the problem at hand.
Maybe it comes off as kind of edgy. Or maybe they're enjoying a preemptive "I told you so - idiots!" victory lap.
This attitude does not make me take your point seriously. It sets off my ideologue detector.