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This is like saying that voltage is a scalar real number, which explains nothing about the physics of electromagnetism, and in my opinion is probably the worst way to explain physics of anything. It especially tells nothing useful given the question is about the stuff that a qubit is made of (which is different from "how do you mathematically represent an ideal qubit on paper?").

And going beyond that, as Peres puts it, "Quantum phenomena do not occur in a Hilbert space. They occur in a laboratory."