80 modern processors have around four orders of magnitude more "moving" parts than a Saturn V, according to what I can Google. And the Saturn V, it is said, had a particularly large number of parts because it was hand-made to an extent that modern machinery is not.

Comparing the number of parts underestimates the complexity of a computer system, of course, because the software is a machine with a vast number of parts, on top of the hardware.

In other words, I'm on the side of those who say software is hard to get right for good reason, and not because the practitioners are less competent.