You mean like the 330 ilvl required Lakshmi groups I see in PF? Comical stuff.
The counter point to this is that I just did a Keeper of the Lake where we kept wiping on the last boss, and everything was taking FOREVER to die. Without a parser I have no way of knowing if the problem is me, the other DPS, or something else. At that point a toxic person like the guy in this thread will get toxic anyway, they just won't have anything to go on.
Hiding data doesn't magically make people nicer. It just makes it easier for bad DPS players to not realize that there's a problem.