The TL;DR seems to be that the power creep of making tanks tankier and healers healier over the expansions plus the dev team trying so hard to stick to the trinity that began to unravel in Gordias to finally seemingly accepting that everyone is a dps despite the color of your role led to where we are now. Current band-aid is removing/combining aspects of all the healing toolkits healers have and replace them with more "interesting" dps abilities while perhaps even nerfing tank sustain a tad(cries in GNB). This would force more healing interaction from healers without needing to ramp damage while also giving them more to do in the downtime between scheduled damage. I have hope in this already looking at how well put together SGE is, we'll have to pray for meaningful changes in 6.1.