"Which I call utter BS on. I doubt Stark could accept the metaphysics, symbolism, and irrationality of magic enough to learn how to light a candle, much less become the most advanced practitioner on earth."

Well, there was that one What-If where he became the Sorcerer Supreme. And he figured out how to integrate magic into his suit with the Thorbuster armor. And he built magic weapons and armor during Fear Itself.

Tony's not generally portrayed as someone who's incapable of understanding magic. It's just an avenue he hasn't really pursued