Have you seen the way people drive? They (we) suck.
You said you drive like a grandma. The guy in the McLaren you saw the other day? He can't drive much faster than you do most of the time, due to congestion, speed limits and road-hogging morons in the left lane. Even if he could, some other moron with a texting addiction will eventually swerve into him or push him through a red light at a busy intersection.
It's inconceivable to me that we couldn't double our traffic capacity and halve travel times if we had the necessary combination of political and technical leadership to do self-driving cars right. All while saving tons of energy, not to mention about 30,000 lives a year. Instead, our best and brightest techies ride a bus to their workplace where they are tasked with finding new and better ways to sell ads on the Internet. Meanwhile, our best and brightest automakers are busy building half-assed "autopilots" that will only encourage people to text each other while camping out in the left lane. To this motly mix, we've added yet more morons who think choo-choo trains are somehow the answer.
Oh, well. The important thing is how easy it is to feel superior to everyone involved. :-P