While i understand the want for more Healing focused healers, this isn't a game where that's all a healer does.
That's also part of the "reward" for getting higher Item levels. It makes your job easier.
I know as a main healer, i don't want to "force" a lot of the game's population to Need to play on a 90% efficiency level for healing. Ive had plenty of groups as a Red mage where i've basically Main healed, cause the healers had no clue what they were doing.
Id rather not make dungeons where its that healing intense where a normal player can't progress.
A bit of a challenge is good. But make it too hard, and it just gets out of hand.
Plus, healers Already get blamed most of the time when a party falls, usually when its someone else's negligence, i don't want things to be so difficult that its actually the healers fault because they lagged for 2 seconds, or were off a second with a cure, or they tried to sneak in some DPS (which is basically mandated now a days)