I guess materialism can't explain computer chips either, seeing as how the state of some of them can allow or prevent signals from others from getting through. As everyone says, "Materialism is the idea that one thing cannot change how another behaves."

Except nobody says that; nobody means that when they say "materalism" (except maybe you).

(Mind is required to be an emergent phenomenon of correctly-configured material under materialism, but it is not required to be an epiphenomenon under materialism.)

If a single universal mind exists which is utterly regular without exception, I agree that it is equivalent to materialism. Materialism is compatible with any form of simulationism; in this case, you would be saying "the universe is a simulation being thought of, without errors, by a 'universal mind'". I might prefer an infinite Turing machine running a particular program, but whatever!

It is in the lack of exceptions, and lack of mind-seeming-simple (you need a LOT of material before you observe any mind-like properties at all), that renders materialism a parsimonious hypothesis.