So all you nay-sayers basically say "idiots will be idiots, with or without douchebag aids".

A damage metre is a major help if you keep wiping to stuff like enrage timers, healers going oom due to too much time passing, etc.
With a damage metre you can see which of the dps isn't pulling their weight.
Don't forget, all the good damage metres in other games can also read how much healing output (especially effective healing), how much mitigated and unmitigated damage the tanks take...

If you want to do hardmodes, and be effective in raids (clearing the instance before 5 months have passed), some form of measurement tool is definitely needed.

Are athletes wanting to compete (at any level) also "elitist" if they use stopwatches, measure scores, how fast they run, etc?