Now, faceroll farming an instance and getting all the best loot is fun too. This, too, will keep a range of people busy for the next couple of weeks.
But what a healthy endgame should do is tie those together. Give people challenging content with the best loot. This will keep a range of people busy for the next few months, and give many people a reason to log in consistently until the next update.
A healthy endgame SHOULDN'T reward an insatiable desire to run the same mind-numbingly boring stuff over and over and over and over again until your eyes bleed or until the RNG smiles upon you and bestows a rare gem.
farming runs don't encourage group teamwork, they don't encourage improvement of self, and they don't encourage a fellowship-oriented atmosphere. They just put 12 random people together as quick as possible and try to button mash to the rewards. Very few farm pugs will distribute loot fairly ensuring some people will be shafted and others rich. And at the end of the day, there's no banter or fond memories of great deeds performed, just an empty desire to acquire another symbol.