the game also tells us how the blight is already changing beyond the gods, with a new song that calls to something else than the gods. The blight is still there, even without the gods and their archdemons. Not only the part that already is in the world and causing the blights but the majority of it locked in that veil prison still
there is a lot more explanation behind "oh this guy was just stealing them" in the game though...like the explanation how they "went extinct" in the first place and how theyre bvack around...