I'd suspect it's partially because they don't know how to incentivize healing. They think stripping damage spells will do it; the problem is more meta than that. It's because they understand how damage dealing works on a basic level, but not healing. Healing has a shelf life. The first benchmark is making sure everyone's topped off, then you start gaining skill by shaving that down. After all, it theoretically doesn't matter if the fight ends with everyone at 1 HP as long as they're alive. On either end of the skill spectrum, there's a point where healing more is just a waste of time.

This is a massive difference from DPS. With few exceptions (such as pushing phases too early and causing party wipes with some sort of early push punishment), doing more damage is always a good thing. You're finished with damage when the entire encounter ends. The problem here is that the job designers are treating healing as if it were functionally identical to damage; doing ever more and more is a "good" thing. This is wrong. We keep telling them this. They aren't listening.

So really... I don't think healing is the problem, the jobs are good and pretty fun... its the ENCOUNTER design that's the problem.
Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare Glare is not encounter design.