I can comment on this.

Hardware is a long and tedious process. CPU design is an extra level of difficult on top.

In my field, it is routine to hire people in late 40s/50s to make CPUs. I'm in my late 20s, and viewed as a weird specimen. In my career I've made a armv8 CPU and now work RV64.

It takes a couple of years to get a guy from uni into working shape. And that's just to teach him how to do 1-2 tasks in his field. If verification, this usually is coverage specification and test writing. Combine this with a cpu project duration average of 5ish years and it's quickly evident that you won't beat someone with a startup.

In my office today, in a team of 10, no one, other than me is under 40.