So why does magic work in Hell? Why does Mephistophleses make deals with wizards to have them perform arcane research in the 8th layer? After all, they are powerless and can't do magic, or understand whatever force is being used in the Nine Hells, since it can't be magic, because Mystra can't effect the Nine Hells, and Mystra according to you, is the source of all magical energy.
In fact, I watched a video on Spelljammer a few months ago. They specifically said that while traveling the Phlogiston, Divine magic doesn't work beyond 2nd level I think they mentioned. But Arcane magic does, because you could accidentally explode everything with a fire spell. How is this possible? We are far outside of the Realms of the Gods, to the point where their clerics are rendered powerless, so Mystra can't be providing Divine Magic.
Are there super-secret Magic Gods just floating between the worlds, in the place where Gods don't exist, providing Arcane magic to travelers, but not Divine?
Again, it makes far more sense that the Gods like Mystra simply provide a framework and filter to make using magic easier, but that Magic itself is more like air. In and around everything, flowing in and out of the environment. This also would explain how some creatures are innately magical, higher concentrations of magical energy in their bodies. Not blessings of the Goddess of Magic, which is what would have to happen, under your framework.
No way!
