The corruption in uldum and the vale is bad but like it isn’t that spectacular. The old god being completely released should have done what the visions are, like from the descriptions we’ve gotten that level of chaos should have actually happened. Maybe just once you entered the raid there should have been more cut scenes showing n’zoth just going all out. Even if we reversed it by killing him, the true magnitude of his ability shouldn’t have been left to him thinking about it. Also I just think the design of the fight is odd. The other old gods we fought were in small chambers, heads and eyes sticking out of the ground. I get the old gods are big boys and can’t just go wherever in azeroth but like, he’s completely free, why is he still just swimmin in a kiddie pool.
The old gods are a few beings that should be more powerful than entire armies, yet some mary sue original character just defeated their whole threat. This should have been an expansion, Azeroth herself should have been awakened, have the titan be born out of the world to kill n’zoth. This was built up perfectly in eternal palace, finally an old god is free… but their dead in a patch.