How would an optional, official parser be toxic?

[Shurrikhan]

have you ever played WoW? unless you want the FF14 community to turn toxic the last thing this game needs is a dps meter

But, parsers increased content accessibility, clear rates, the predominance of well-informed rotational guides, and--with those--the cross-class and mechanics-common knowledge useful for both advising and synergizing with other classes... ultimately resulting in... reduced principle toxicity...

In all but tight-enrage, Kiljaeden-esque fights, it's not your numbers people are going to be pissed at in WoW. It'll be your failure to CC, interrupt, or LoS the enemy's near-one-shot skills, CCs, or massive heals. That isn't a parser issue. It's a 'actually giving a modicum of real responsibility even in (heroic) dungeons' or 'there exists a difficulty for which not everyone is immediately ready' issue and its benefits have outweighed its disbenefits. And it's only because the content is so damn easy in all regards but DDR and DPS-checks in XIV that damage ends up "making or breaking" a player's worth, and even then only in the context of the same content they'd "break" for their party if they don't improve.