Because in general, the people with experience in the sectors he talks about will want a position of power, and aren't interested in working with their hands. B

Because in general, the people with experience in the sectors he talks about will want a position of power, and aren't interested in working with their hands. Business owners want to hire these people (I won't place a judgement on the decision itself) and therefore need to have the open positions. Things are changing though, at least in the tech sector.