See, this is what I don't like and I feel is where people can be narrowminded when it comes to games that use the triad of "healer, tank, DPS". Different games will approach how that triad works differently and not all of them will use the exact same philosophies and I don't like that people come to this game and then expect this game's philosophy to change. The game is designed to benefit from healer DPS, it encourages it and at the higher tiers of content, needs it. I joined this game happy with the design philosophy and fell in love with healing in this game and now in its current state is dull as heck.
And it was a design that I feel complements the series as a whole. Because Final Fantasy hasn't generally been so rigid in such clear cut opaque definitions. Generally in an FF title you will find times your party doesn't need healing, in that time your healer character will have other things to do. This is a philosophy true of their single player games and philosophy true of their MMO's.
I played SCH in XI as our static's main healer, that job was plenty complicated and had a LOT and I mean an awful lot to do in its downtime and had a lot of DPS abilities and probably the biggest ability pool in the game. Whilst XI is a wholly different game, I love that they retained the philosophy of giving you more to do in your downtime when you're not healing. And now it's dull as heck.
And honestly, for people who struggle to keep up with healing and DPS, personally, I don't mind if they sacrifice DPS or just DPS sub-optimally, just as long as they're not being lazy when everybody else isn't. In fairness, for a lot of content, DPS helps but is not required. I was the same when I was still new and newish to the game, once more became second nature, I appreciated that I had more I could be doing.
IMO, they had the balance right for DPS/Heals in ARR and HW. So no inevitable shifting to being DPS that has the odd bit of healing. After all, it is not how many DPS abilities you have that affects DPS focus it is the content and how well your healing spells handle it that affects your healing focus. By adding things to restrict DPS or make it less dynamic, it doesn't make you do more healing, it just makes you more bored.
Blue Mage with 4 healing spells and a butt load of DPS ones has more of a healing focus in healer stance than any real healing jobs.