I am planning on running a homebrew campaign, whose ultimate premise is that a villain is attempting to garner enough power to be able to eliminate all magic from existence.

I am planning on setting this in the Forgotten Realms, but to avoid any confusion, I am excluding any of the other settings/realms from the equation (Grayhawk, Eberron, etc) to spare myself the headache of how a change of such scale would affect other realms.

I am aware that a lot will have to be done for someone to be able to achieve such a goal, but that's a question for another day.

So, mainly, what happens with the entire removal/deletion of magic from the Forgotten Realms entail? Would Elves disappear, owing to their magical nature? What about dragons, and other magical creatures as well, such as the fey? Would the planes "collapse"? Would they cease to exist? Would only the Material Plane remain?

I know that I can simply change things up a bit in my homebrew to accommodate my vision, but I would prefer to first go off a bit of established lore.