I wonder if the next step in the evolution of public transport is something akin to Uber. It may be more entropic come the day self driving cars come along.
Given that each car heads to its destination without a transit route where passengers are buffered would be good.
Additionally, since the road is shared unlike the subway, it may be more efficient on resources.
Perhaps when the option becomes available, the government of some affording country may be able to pilot such a thing.
The big problem is scale. You can replicate the capacity of a smaller bus route with efficient self-driving cars, but bigger routes and higher-capacity transit move tens and hundreds of thousands of people per day to a destination, and loading/unloading capacity near those destinations is just not going to fit.
Demand is already centralized both geographically and time-wise, with business districts, downtowns, rush/peak hour. Self-driving cars might replace feeder networks but they'll only strengthen the case for high-capacity trunk transit.
Some numbers for context because I was thinking about it. Let's say it takes a person five seconds to get in a robocar at an organized terminal area (car pulls up with door already open, people are lined up - getting in on the street in front of a building would be slower). Let's say you can weave five terminal lanes into one traffic lane, so cars can leave the terminal at about 1 car per second per lane. In five minutes you can ship out about 300 people per lane.
In those same five minutes, a Calgary C-Train would have pulled in, loaded, and departed with capacity of about 700 people. Or three Skytrain trains, each with capacity of about 500 people. Or two Victoria Line trains, each with capacity of about 1000 people (non-crush load). Or two double-decker RER trains, capacity over 2000 people each. You'd need a lot of robocar terminals...
Given that each car heads to its destination without a transit route where passengers are buffered would be good.
Additionally, since the road is shared unlike the subway, it may be more efficient on resources.
Perhaps when the option becomes available, the government of some affording country may be able to pilot such a thing.