I can understand asking for more healing too instead, but I don't think people are being realistic when they demand it needs to all go away (and not just nerfing individual broken skills). Removing tank sustain won't fix anything unless you practically take it all off, which doesn't seem likely. To really make healing interesting you'd have to do more than rebalance the jobs themselves too and rework every instance. At best a couple of fights are going to get tiny changes to their scripting, but that's all it's going to be. It's frankly incredibly unlikely even when they make a whole new batch of encounters next expansion. I just don't see the entire paradigm changing like that mid-game or them going back to rescript the old content to make it match.
And getting hostile over the notion DRK should be brought up to at least something resembling the other tanks is just some weird cycle of abuse thing. Being bored 80% percent of the time but once in a while a DRK shows up isn't the right way to "keep" your role interesting.