I'm curious about how you feel that this is lore correct?
From the angle of in game lore, the White Mages of Amdapor went toe to toe with and beat the Black Mages of Mhach, the fall out from which was destructive enough to cause the fifth umbral calamity.
It's not even much of a Final Fantasy trope. Healing focused roles in classic FF games have historically done just fine on the offence, usually being defensively frail rather than offensively inept. FFXI is a notable exception but then the same can be said of just about any job that isn't the right job for the situation, it just kind of ran away in it's own direction with Nin tanks leading the charge.
As for other MMOs. Claiming that this is somehow 'the bread and milk that formed group gaming as we know it today' is just laughably misinformed. Have you ever watched an Everquest Druid soloing drakes in Cobalt scar? 4 at a time btw.... If you looked down below the cliffs, you'd see a Shaman killing a raid boss called Kelorek Dar. Solo.... The irony is that if you actually go back to the game that stamped the MMO trinity that we have today, tanks and pure melees were the helpless ones that needed ferrying around, not healers
So where does this come from? It feels like you're just taking the word 'healer' literally and assuming that the job should have no other facets or depth to it beyond that?
What? At what point are you referring to? Nobody really understood the game in any real depth in ARR. Coil DPS checks were rare and mostly lenient. The only people who I ever saw get called out were those that genuinely did stupid things like melding or pointing a stat that they genuinely couldn't get any value from. If you're referring to HW with Gordias and to a lesser extent, Midas I can appreciate your point more. Gordias was a *HUGE* shock in terms of the DPS it expected from players, especially after Final Coil. People who were stepping into Savage needed every bit of DPS that they could get their hands on, healers included. ThordanEX was a bit of a wrecking ball as well, so yeah, I can well see this spike in damage requirements filtering down out of the raid scene in the same way that the whole 'Exclude WHM' thing ballooned way out of control in patch 3.5.
Hamstringing an entire role just because certain aspects of the player base are idiots isn't a particularly sound design choice for the long term.
Again, this is why I keep preaching that SE should take AST's buff system much further. Let them spend GCDs on cards and balance it from there.
It's not the number of abilities that's the problem here, it's the fact that we press 1 of them routinely 200+ times in a single fight.
I'd be saying exactly the same thing if we were pressing Cure 1 as frequently.
God forbid we expect SE to actually improve our little corner of the game. God f**king forbid.