The supposed support role is P.Ranged. I'm not sure why no one has brought this up yet. BRD pre-SB had support tools and so did MCH. IIRC BRD had MP regen and MCH had TP regen. You supported your party in that way but you also did your dps duties. BRD now has an Esuna, all three have a AOE defense buff, DNC has a heal and MCH now has Dismantle. I think they could have more tools to support like they do in PvP but for now, they're adaquete.

Do I then want to play any of them because I have more to do? No.

I see MMORPG, I play healer if its offered. Support classes are DPS classes. They're not healers. They aren't even combat medics or dip into triage. They may have enough spot healing like RDM and DNC, but as DNC and RDM are DPS here, so are support classes in general.

And before its asked: would I want a pure buffing/debuffing class, no.

What I want is a healer. The problems are:
  1. healing is boring in this game due to how similar healing styles are between classes
  2. healing is boring in this game due to how encounters are designed
  3. healing is boring in this game when a non-healer class (WAR) can replace me because #2
  4. healing is boring in this game when I group up with another healer because #2 doesn't factor in having two healers with bloated healing kits
  5. healing is boring in this game because when I have nothing to heal and everything is fine I have nothing to do - no buffs/debuffs to manage, no intricate dps kit, no mp management, no cooldown management

I would be fine if FFXIV went from the crap its doing now to a WoW styled model with more incoming damage that is unpredictable which makes it harder for me to do my 1 dot 1 nuke spam, but it still doesn't fix the issue that:

the devs want this to be a more solo rpg and healers in solo content are shite because they have mostly a DoT and a nuke and 20+ healing tools that they don't need or that if I get good enough with my healing tool kit I am rewarded with my DoT and nuke only because see #5.