> And it's doing this while using more than an order of magnitude less power (10W vs. a TDP of 125W for that Intel part).
That's the wrong conclusion to make. For instance, the Lenovo ThinkBook 14s (with a Ryzen 4800u) with a 15W TDP posts the same Geekbench multicore scores [1] as the M1 Macbook. But the ThinkBook isn't in any way faster than the top-end iMac for real world compute intensive tasks.
The M1 certainly looks efficient, but there's little you can conclude from a single benchmark running for a very short period of time.