That has nothing to do with the point Stormphoenix is making. Take away that immunity (which we don't know the limits of) and Adversary isn't that impressive. We are talking about raw power, which both Franklin and Molecule Man eclipse Adversary in. Goddess Storm beating Adversary does not mean she could even touch The Griever, it's apples and oranges.
It's like Pokemon match-ups. A level 50 Ghost type Pokemon can't be affected by a level 100 fighting type, but that doesn't mean they are as strong as them.
Storm has shown nothing that puts her on the same playing field as Franklin, Molecule Man, and The Griever.