[marcinzm]

How exactly will it reduce congestion? The cars are the same size. The trips are the same and are likely to go up in frequency with self-driving. The roads are the same as before. If anything you will have a ton more congestion. The vast majority of congestion is due to not enough capacity and too much demand. Right now that is caped due to the time you waste driving but if it's self-driving then the sky is the limit.

Public transportation increases the potential commuter density per area of road/rail while self-driving doesn't.

[warcher]

I think self driving and public transport are actually complimentary. The principal benefits of owning your own automobile are convenience, as it’s always available for your use, and range— it will go wherever you want. Enabling vast fleets of on demand taxis is already well underway, making owning your own vehicle less attractive. The next step imho is bundling rides together, making NOT owning your car cheaper still. For urban cores, I would expect shared self driving to crowd out private cars pretty quickly.