You can still only fit so many cars safely on a given road, regardless of how automated they are. Subways (and all public transportation) will always have great

You can still only fit so many cars safely on a given road, regardless of how automated they are. Subways (and all public transportation) will always have greater potential throughput, provided that people can get where they want to go. The larger the city, the more likely you are to have common routes with other people. It's analogous to small packets vs jumbo packets. You're going to always have better throughput for the overhead, the larger the unit... so for just bulk moving of data (people) to/from a limited number of destinations, you'd be better served with the "jumbo" option. If you have a small number of people with a large number of destinations, a smaller option (cars), is better. Unless we're talking completely reimagining the transportation network (which isn't a 5-10 year time frame project), you won't see use of autonomous pods displace subways -- especially in a place like NYC.