He addressed this point: you'll be able to drive yourself but it'll cost you much more than giving the control to the car (due to cost of the insurance) and much more than today (insurance spreads risks and in order to work, needs a lot of buyers, in this case drivers; if most people switch from current "person driver", expensive insurance to much cheaper "auto-driver" insurance, the "person driver" insurance will become more expensive because there will be no benefits of scale).

Ultimately, it doesn't matter what you will do, but what majority of people will do and his article is about those big-picture changes. Cars replaced horses as mode of transportation, with many consequences to society. Very rich people can still ride horses as a hobby, but that doesn't nullify the magnitude of changes brought by replacing horses by cars.