"healers say they're bored so we'll increase damage", usual simplistic view from Yoshi :|

He's not wrong ; just trapped in his own shallow game where healing has become some kind of side-activity because of the focus on one-shot.

If they want to make healing relevant : Ban one-shots, and start over from there.
Or, commit to what you're doing and transform healers to "green dps". It would be stupid but at least the jobs would be slightly less boring to play.

As shown by some answers in this topics ("don't use better gear", "sync gear"), FFXIV trying to keep a RPG paint-coat is becoming more and more ridiculous, since part of its players base don't care or don't understand it.