Whomever wrote this is a fool.
When you need a car, truck or whatever, you need that mode of transport. If all you need is to move your ass down the street a short way, a bus is helpful. Walking works too. And In so many cases, walking is faster than a bus -- why don't you walk fool?
They are not the same, not even remotely.
what driverless cars can replace is commuter vehicles, especially outside city cores. They will be more convenient than zip cars (in the current state) or the like, after all they come to your door. A bus doesn't, unless your door is where the bus is. Owning a car may seem ridiculous if you order up one, step outside and its there for you - drops you off at your destination and goes off to help another traveller or 2.
By the way, who says it has to fit more than 1 person? or more than 2 peopel?
How often do you travel with more than 1 person? I know my answer. 1%
What's your time worth? I know my answer.