This. Now WHM/RDM can just take care of themselves.
The problem lies in that what once was the domain of a specific job, what made it valued- has become something subjobs can bring to another job instead- and nothing in the 76-99 range has replaced them, which narrows things down. If I was the devs, I'd be looking at abilities and spells in that level range that make people go "Oh, THAT'S what you need <job>" for!
If content becomes nothing but DPS + heal vs. monster, then logically that's what jobs get the nod, every time- along with whatever (staggers/TH) generates the most loot. Everyone else gets left on the doorstep.
The solutions are many, but one part of the problem is that so much of what makes a given job unique was allowed to bleed into subjobbing it. Being able to mix and match a lot of L35+ JA's and such was the wet dreams of many a L75-era player, and lo and behold it happened.
Make the jobs unique again, or we're in the MMO standard holy trinity of DPS, tank, heal + guy who pokes the mob for TH.