It's the vanity , self praise and impression that " I did it all by myself " that irks fellow pilots.
.... ain't that the guts of it . . .. and anyone who says it matters nil about who or what is the person behind the mask, as opposed to his performance, is naive. (and probably can't get his hand off it as well.)
Go to the accident reports that reveal that tension and animosity on the flight deck led to incidents or worse. In my own experience, a month with a narcissistic, arrogant, superior person was enough to make one want to run away.... run away. . . at least for a few days at the end of that month.