Well I believe it was the pilot that read back "position and hold" as the controller initially said "line up and wait" and then corrected the pilot, who then said he liked "position and hold" better. So it's not the "...(unprofessional) controller," rather, it was the pilot.
It has not exactly been an easy change for those who have been saying it for years on end. It wasn't just a one or two word change, it was a complete phraseology change... which isn't as easy as turning a light switch on and off.