But that's exactly what makes no sense. How can you even do that as a healer to begin with? And tanks don't have a few buttons. They have completely fleshed out dps rotations.
As for tanks having a similar lvl of responsibility, it highly depends on the fight. If there is a body check and both tanks are dead yes, otherwise I don't agree. If both healers die and no dps can rez you have to reset(that is also very often true even in trash content). The incoming damage sustained by the entire party from upcoming mechanics will not be mitigated or survived for that long.
"Also healer is definitely not the most complex job, I'd sooner turn to a handful of DPS jobs long before I point to healers as complex. If you know to prioritize oGCD heals over GCD heals, you've already mastered 80% of the role."
That is grossly not true and only applicable to very few instances when everyone knows the fight extremely well and 0 mistakes are being made, otherwise no. You clearly have not played high end content if you think that's all it takes to be a healer..lol