I'm a bit baffled that Google indulged in this silly game. Quantum supremacy is eminently a non-empirical claim. You need to prove it theoretically: here's a lower bound for classical computers, here's an algorithm for quantum computers that beats it. Then it's open and shut. Claims of the kind "we ran a certain algorithm on a classical computer and another on a quantum computer, and the quantum one was faster" are pretty worthless. Why did they, and Scott Aaronson for that matter, go with this game of naked emperor?