>So yeah, the machine has "insanely good IO", and once the rest of the world catches up it'll be even better.
I mean, that's the thing. Apple jumped ahead, and USB-C just isn't common. (At least, for me. I can't name any device I've used or even heard of that uses USB-C.) So, it's a less than practical option if you're in the market for a laptop, not so much insanely good.
I wouldn't buy a computer with only serial and parallel ports because none of my devices use them, and I wouldn't buy a computer with only USB-C ports, because none of my devices use them.