Back in the 80s, Don Norman popularized the term affordance. Humans need something to push, pull, turn or otherwise interact with. We are physical beings in a physical world.
Driving vehicles is potentially life-endangering. Just because the technology is there and cheaper does not mean that humans can push aside their physiological limitations in a critical situation.
Take the emergency blinker. You know where it is, you see it all the time - it's right there in front of you! But when a real emergency happens, you'll be fumbling for the button, concentrating on the situation at hand. Now imagine that button on a touchscreen.
Thanks. Damn autocorrect.