“The semiconductor industry thought about it decided silicon was a better material platform 50 years ago.” Because we’re stuck at a handful of cores and around 3ghz clock on silicon.

We are? I must not know how to count because those are not the numbers I have. What year is it where you are?

The decision was kind of arbitrary though, and now economy of scale makes it very hard to switch. For instance, GaAs is better semiconductor than silicone in many aspects, and probably somewhat better overall for chips, but switching to it would cost billions