Instead of focusing almost all of their development time on elite end game activities, they could have worked on features that only MMO’s can do well. Social features. Player centric story features. Archeage did this masterfully, so much so that one man has put his fortune on the line and is developing his own MMO to recapture the magic of that game, Ashes of Creation.
I still have memories from these game features that are far more lasting than anything to do with some in game story. That was the beauty of vanilla wow. But they dropped the MMO philosophy and instead turned wow into a loot centric diabloesque lobby game.