Any argument against personal parsers is, frankly, stupid.

It would literally harm no one to be able to see how much damage you, personally, are doing per second. Then you can just have a letter grade or w/e to tell you how good you are doing when you wipe or even as the fight goes on. This does nothing but give the player more information that will better help them improve as without a number they've no idea how far off they are from where they need to be.

I also don't buy the argument against parsers in general. We already have them, PS4 players just can't use them. People apparently don't realize it, but you don't need to say "you are being kicked because you are doing garbage DPS" - you can just say "you are being kicked because you are under performing" (or you can literally say nothing and kick them). We would literally gain no toxicity from adding parsers to the game, if the game were to be toxic with a parser then it already is. The only thing adding a parser would do is give everyone the same level of information and probably increase the skill of the playerbase since now people actually have useful information.