The first question is is the type of people who would be displaced by this technology the same type who could shift to being lawyers and engineers? (My guess is the overlap of would-be truck drivers who could also be engineers or lawyers is very small.) The second question, taking for granted that the answer to number one is that truck drivers and highly educated/trained professionals are very interchangeable, is at what point are there too many engineers and lawyers for them to be productively creating value for the economy?