To be honest, I don't get people that expect WoW story to make sense. Not only it has limitations of MMO, but it's also so successful it's de facto endless story (in sense that devs can't really plan how to wrap up WoW right now). Never saw TV Show with good writing that last more than 6 seasons (usually quality of writing drop long before that) and Warcraft has over 20 years and 13 'seasons'.
That's why from WoW story I expect cool characters and events, not plot that will blow me away. Sometimes they deliver.
Btw, Warcraft III wasn't a masterpiece neither.