Kind of sad to think about. For most ardent WoW fans, the meat of the lore was from Warcraft III; Legion and Scourge. Warcraft 1 opened the door but 2 and 3 kicked it down with Legion and Scourge stories. In many ways, The Legion and Scourge no longer being the heart of Warcraft's conflicts is like Batman losing The Joker and new villains being created. Yeah, the story must go on, but in many ways, it'll never be as good as it once was.
Then again, Mists of Pandaria showed us new lore can be just as good if executed well.