If anything self driving cars will be most disruptive in trucking and delivery and in the process destroy the economy of middle america [1]. As for everyone having an on demand car, it has been stated here a number of times that most people still all need to get to work around the same time. If anything, automation and robots are a race to the bottom if we stick with capitalism in its current form.

[1] https://medium.com/basic-income/self-driving-trucks-are-goin...