Nobody says that matter can create. But maybe what goes to make up matter, antimatter, dark matter, energy, gravity, etc., simply exists and, in the process, creates and destroys by reason of its nature.

What's been "demonstrated as false" is not belief in God, just the assumption that the existence of God, and His interest in individual human beings, is needed to explain the universe.

The existence of the Greek and Roman gods, BTW, has not been disproven either.