I don't see how his ventures could have made the progress they have with a business/finance/sales person calling the shots. Elon is adept at engineering; you can see it whenever he is interviewed and goes down rabbit holes about metallurgy, simulations, manufacturing, etc. The achievements of Tesla, SpaceX, Starlink and others would not have happened without thousands of correct evaluations of and decisions on technical matters, and Elon is the singularity around which all of that orbits.