Tanks should not be the immortal self-healing gods that blizzard has turned them into this expansion. It’s absurd the extent to which they can solo content inside dungeons after the rest of the group has died. I realize that some tanking classes were designed to use self-heals in-place of classic damage mitigation, but this has gone way beyond that.
Having a huge component of a healer’s role in group content become trivialized is only part of the problem. The other part of the problem is the disconnect that now exists, from the tank’s perspective, between the amount of incoming damage and what the group can actually handle.
One of the MAIN reasons why healing sucks so bad right now, on top of the double-nerf that all healers got hit with, is that tanks are so powerful now that they almost always over-pull in dungeons. And when that happens, even though they caused the problem, they are often the last one to die, or even survive long enough for the rest of the group to run back. Some of them have even let it go to their heads to such an extent that they aren’t even willing to admit that they did anything wrong when this happens. The healer often gets blamed instead.