So is Bitcoin not evidence of quantized time to you? If not, what exactly is a block?

If continuous time were fundamental, why do non-contradiction (no double spend), state validity, and finality require discrete blocks? Why does Bitcoins fundamentals collapse unless time advances in indivisible steps?

Either discrete time is essential to preserving consistency, or continuous time is doing no real work here. Which is it?

That is literally the axiom you are relying on here.