“Things you can only do in a fab” is but a subset of “hard problems in EE.” How many people actually understand induction motors well enough to design a better one? Or how about antenna theory? The math makes most people’s eyeballs melt, and the space of possible antenna designs is utterly unfathomably huge. And then there’s acoustics, which is just like antenna theory except the math is sideways. I could go on. Control theory. Analog signal processing. Digital signal processing. Biomedical.

I say all this as a recovering semiconductor engineer: EE is a huge field. I can’t think of a subdiscipline where we’ve run out of new ideas to explore, and most of them don’t require bucketfuls of HF. The real problem is that the financial rewards are relatively small, the math is ferocious, and there are so few practitioners, let alone experts doing research.