I'll say what I said in another thread on the note of parsers:

The world and social network in this game isn't going to suddenly come crashing down because of the addition of a damage meter. People will be jerks regardless and I think the impact people think it will have on the community is a bit overblown. You're already beholden to a standard without parsers (ilvl and experience), the only thing this will add is that you will have numbers to back up your standing or not, because let's face it, people can get higher ilvl and still have lots of room for improvement, to put it kindly.

Getting mechanics down via practice is good and all, but you should optimize your DPS along with it and not having a meter really leaves it up in the air of how well you are performing and how consistent it is. It's a matter of better telling you what direction to go in terms of where you can improve. In the end, mods don't kill game communities, and this type of harassment isn't as prevalent in games that have a meter available as people claim.

Be it personal or not, having one in game would be advantageous to any player.