Sure. You need tanks and healers to queue in, and their population numbers are smaller than DPS. That makes them a "valuable commodity". But most people want to be more than just a warm body. I'm talking about being valuable in the sense that people respect your skill as a player on the job. That only happens when there's a skill differential, which is what you're asking for here.
You can really only correct mistakes to a point. For a lot of mistakes, the penalty is either less damage, or player death, which also translates into a damage loss. And in the latter case, raises are so ubiquitous and you don't even need to be a healer to perform one. And I suppose that's where part of the problem exists. Because raises are trivial, it's an expected outcome. It's not precious: this is not a 'once every ten minutes' battle raise. There's nothing to celebrate; everyone knows that you've lost raid damage because of the death and the damage is done. The raise is merely the inevitable follow-up event that nobody bats an eyelid at unless you somehow mess it up.
While you won't surpass a the very best DPS players in terms of damage output while on a support role (as should be the case, or else we'd run only tanks and healers), there definitely was a lot more overlap in earlier expansions than there is now, even when comparing at relatively skilled players. Actually, if you want to look at a time before raid buffs were so prevalent, in late ARR some of the best players at the time got together and scribed in their abacus totals on a mottled excel spreadsheet that's still floating around the internet, if you know where to look. And there definitely was a lot more overlap then than there is now. Which is hardly difficult, given that there is none.
I think for long term satisfaction, you need to see some degree of personal growth as a player. That in turn requires a meaningful skill differential that impacts your team's performance. A novice player should see someone more skilled and want to put in the hours of practice to become that player. That could involve having more dps complexity for tanks and healers which translates into a significant raid impact. The dev team is not at all interested in this, and the STR accessory fiasco in Stormblood should have clued people into this if they weren't already aware. Tanks are there to take damage. Healers are there to heal damage. Yay.
Working under this constraint, you have to suggest something that allows you to be challenged and allows for a skill differential in the role. For tanks, I think that could come out of allowing more control over boss positioning and movement. For healers, I think that could come out of having greater variability in fight damage patterns, unpredictable damage spikes, and more challenging resource management, but I don't see any simple solutions here. Well, aside from the obvious, which is swapping to DPS. Hey, did you know that they'll be doing a media tour/live letter on Reaper, the new healer job? Looking forward to it!