It depends what you mean by "specialist in microprocessors". There is enough publicly / academically available information about CPU architecture / microarchitecture to become highly knowledgable on the subject without ever having worked on a CPU before. But once you get to the level of implementation, physical design, and manufacturing, you need real specialists, since all of the relevant knowledge only exists in industry.
I think that the whole point of parent comment was that you need specialists to create that "publicly / academically available information" im the first place.
