Your previous example was Shield Samba/Tactician/Troubadour. Which are literally the same skill except for the animation and what level they're learned (and BRD, the one who originated the skill, gets theirs LAST currently, sadly enough). That's cookie cutter. That's homogenization. Tank invuls are a better example of things that still allow for distinct and meaningful differences in a skill while still enabling the function across a role; I find the HW refresh mechanics to be dubious on that account.
If they're allowed to be useful? Great. But how far can a skill be pushed in relevance before it becomes "role defining?" I'd rather not see all possible support skills either be terribly weak or have to be role skills.
There are other games that have managed to find balance in diversity. FF14 isn't those games, but there's nothing that prescribes the present rigidity of capability it has even among the Trinity MMO subgenre either. Especially if the bigger definition of the role, raid DPS, is allowed to be more uniform across jobs and thus ceases to be weighed against a job's non-DPS support capabilities.
Everything warps DPS balance. Better healing and mitigation frees up healer GCD's. Better movement options make it easier to retain uptime. In this game, at least, it usually pales compared to the baseline DPS of a job. If baseline optimized rDPS can be brought more in line across DPS jobs, there's a lot of design spaced opened for new support abilities without unbalancing jobs completely. Given that weakness heavily penalizes DPS anyways, and some mechanics will just wipe the party if you fail, in the context of actually clearing difficult content I'd dispute the true potency of raise on preserving DPS. Clearly it hasn't been enough to justify RDM over BLM this expansion, and multi-rez wasn't enough to make RDM PAR with one-rez SUM during the latter's height in StB.
I'd rather see BLM get removed from the role, and put into a new role with SAM and maybe MCH, than get a raise move.
I don't think that's an adequate solution. I have a problem in general with raid buff rDPS jobs having less rDPS than selfish DPS. It's not as much an issue when your role is straight support or something like healer (though, debatable in FF14 given how they've chosen to balance WHM and the powerful focus on DPS'ing as healer). When you're a DPS, and a chunk of your DPS depends entirely on other players, and even at your and their BEST that doesn't take you above someone who can bring more independently? That's an issue.
Of course, the selfish DPS need their place too, which was the issue in StB. And the only real solution I can see if making optimal results from buffing only possible if you have a selfish in your party.
Also, by the gap, do you mean the absolute number or the percentage? Because if SE insists on maintaining a rDPS gap between jobs, basing it on the absolute number becomes increasingly meaningless as expansions and gear march on. I don't have a strong opinion here, but I do note that I see players saying the gap needs to go back to the exact number it was, while ignoring that now our DPS is about double what it was end StB.