[AlanSE]

It works well in some circumstances, but not in those circumstances. In places where it does work, urban development had to change to accommodate transit. All of the existing development and infrastructure is so inflexible that these particular metro areas have no choice but to have the transit system change to accommodate.

The requirements seem pretty clear to me. The system has to be on-demand, able to accommodate sprawl, and lose little in terms of average speed compared to old expectations of personal car transit, and most importantly, it can't demand new physical roadway infrastructure.

I see how it's dubious that autonomous vehicles will fit this bill. Or it may be very challenging and take many decades. But let's be honest about the situation - it's the only option on the table.