People getting harrased for their DPS does happen, a lot actually. I entered a Fractal run not long ago and the tank literally told the DRG that his DPS was horrible, that he was completely 'F-wording' up his rotation and was generally just being obnoxious towards him. The DPS was fine and it was a Fractal run. Extremely unnecessary and they kicked the poor guy.
A personal parser would be good but otherwise I can see why SE wouldn't want to add one. Some of the FF community can be pretty harsh.