I feel the need to consolidate a few prior posts into something more succinct, because it is an important observation I think some people in this thread haven't grasped:
FFXIV, with every expansion, is moving closer and closer toward an action RPG combat model. By that I mean it is more about attacking and dodging than it is about strategic ability selection on the level of FFXI's elemental weaknesses or GW2's condis/boons.
The inherent structure of action-oriented gameplay makes healing an ancillary feature, not a necessary one. In action games, dodging (and to a lesser extent shielding) serve as the primary means of defensive/reactionary gameplay that healing serves in other types of games like turn-based RPGs (and, if we wanted to dig even deeper, even in a lot of turn-based RPGs healing can be a fairly optional role with sufficient strategy and pure healers are typically shunned for jobs with more versatility and damage options).
What a lot of "healers should heal" proponents simply do not seem to grasp is that, unlike doing DPS which is mandatory, healing is not and will increasingly fail to be a fundamental, full-time job in an action-oriented MMORPG. The devs can make jobs as beefy or squishy as they want to create some vague need for a tank role, but they cannot create enough situations that *ensure* that healers will actually have (fairly dealt) damage to heal when most of that damage is preemptively addressed through dodging or shielding. Healers in action games are *failsafes*, not *fundaments*.
This does not necessarily mean that healers *need* to be DPS. They could *in theory* take on a buffer/debuffer role, and perhaps there may be room for that in an action-oriented game. But I think just looking at the game's design sensibilities generally it just seems that every job wants to be DPS-y, based on the meta evolving toward kill speed and DPS-checks, and the aesthetic increasingly favoring very flashy weapons, even for healers. And either way, DPS or buffer/debuffer, healers are long past the point where they can sit on their hands and wait for heals--they need to be doing more and be allowed to do more than healing in order to justify themselves at all. I think calling them "healers" and not "support" has subconsciously pigeonholed their design into a place that is becoming quite incompatible with FFXIV's overall combat design.