I love walking as much as anyone. And I love efficient and convenient mass transit, but I realize that there still is a place for cars. Tokyo, Paris, etc. Very good transit and very walkable, yet cars are still necessary. With autonomous vehicles we can utilize capacity better reducing the number of vehicles necessary to transport a given number of people.
Yes, I know, I know, suburban sprawl, rural communities, etc. But rather than perpetuating car-centric design and the inevitable, though fewer, deaths, maybe we should concentrate on designing walkable, bikeable, liveable cities instead.