Sure they could have buffed it.
They could have done it SB and they could have done it in ShB.
But they didn't and were never going to, the fact that they outright removed it is proof enough of that.
They don't like significant and reliable self healing unless its a healer because they don't want you to cheese your way through your punishment for screwing up, it's the same reason potions have never and will never restore enough hp to matter in raids or trials.

Red mage is a special case though.
It goes against what I said above, but take those things away and it's not a red mage anymore.