Storm outpowers most of the other "gods" on her own even without this, though. That said, I don't know if it quite works the way you say. The Orisha were not originally "gods" and "goddesses", for instance, but they evolved into that because of the beliefs of the people. I don't believe that once the power was unlocked in them that it could simply just go away and they return to what they were prior to their ascension. The same would apply to Ororo.