You extend to me quite a bit of courtesy here, and your tone is very generous although you disagree with me. I seem to see a lot of posts these days that skip the courtesy (which is necessary for productive discourse, rationality is about winning, etc.) and start with "You're wrong" and then proceed from there with middle fingers raised. I do think most of these are relative newcomers, as you say.

This reminds me of Cynical about Cynicism where Yudkowsky writes:

Which in turn means that rationalists, and especially apprentice rationalists watching other rationalists at work, are especially at-risk for absorbing cynicism as though it were a virtue in its own right - assuming that whosoever speaks of ulterior motives is probably a wise rationalist with uncommon insight; or believing that it is an entitled benefit of realism to feel superior to the naive herd that still has a shred of hope.

People here can be blunt for the sake of getting to the point, or can at least appear blunt. This could make it look like "rationalists are blunt," which makes people blunt for the sake of signaling rationality.