Parsing would, however, make things objectively worse in places where parsing is not really needed.

What's to stop people from using the parsing in places like the Leveling Roulette? I mean, if we wipe on a boss, am I going to be told I wasn't DPSing enough as a healer? Or maybe I'm trying to learn how to play DRG in the lowbie levels and I'll get berated for not doing good DPS?

I don't want that crap in my FFXIV.