Even in cities that currently have underground rail systems, I think public transport within cities is inefficient. So much time is wasted stopped at stations, and not going directly from your origin to your destination. If the tunnels were paved and road ramps to the surface added so that robotaxis could go down there to avoid the disruptions of the surface, so much time would be saved. Yes, autonomous driving is not good enough yet, but Waymo and the latest Tesla FSD version are undeniably not that far away, so I think cities should start planning for it now since it will likely be a reality within 15 years. It frustrates me that no one in my city's management seems to be thinking about it at all and are instead planning to restrict car access and invest billions in new rail systems that won't be ready until around the time they will be obsolete. They talk about the space used by cars compared to buses/trains without considering that most robotaxis will probably be tiny single occupant vehicles that aren't comparable to today's cars.