Just because all the "lore" (<- I use the term VERY loosely) is being spat out by one dude for the most part and fitting into his personal fantasy vision for how things should be doesn't mean it's the best lore or story that can be told. Far, far, far from it. Someone with an actual talent for storytelling could've taken WOW's story to so many better places in all the years they've had to play with it.
Honestly it's like asking if Star Wars can exist without George Lucas. I mean yeah, he created some initial shit that was pretty tight (even though it was essentially any fantasy setting ever made, but "in space") but he lost his touch pretty quick and has made nothing but shit since. And now that he finally sold the rights to someone else, they have the potential to make it better. Or worse. Remains to be seen. But it's hard to beat lucas's latest attempts.
Point is in the right hands, either franchise could improve dramatically over their current iterations when chained to their current dictators.