What if the orcs never left draenor Edit

What if they never went through the Dark Portal? I mean if so alot of important people would have lived longer like Durotan, Ogrim Doomhammer,King Llane, Lothar. And the alliance would have ben the only real power in the world. The seven kingdows would still probably be there. Now when the time came when the Burning legion made its return, There would be a better chance of the alliance winning because the horde wasnt there to kill Cenarius. So I think if the horde wasnt there to be for the battle of Mt Hyjal the world would have prevailed with less losses in lives Invisobills