So Sargeras succeeds in destroying Azeroth and all the worlds in the Great Dark Beyond.
Afterwards he destroys all demons as well as the Twisting Nether and then with so much Power gained from these events, Light and Darkness as well.
Then he stops existing because there is no force left which can maintain him as he started out as mere creation too.
So everything is back to square 1.
Over time a new world arises with entirely new gods and creatures which inhabit it - WoW 2.0 (with better graphics)
Would you paly under these conditions? (Note: It won't be Guild Wars 2 or Rift
)