I think that is the problem. Transit agencies and "urbanists" are too stuck in their ways. Transport is changing. Much in the same way that airlines are moving away from large aircraft and hubs to smaller point to point flight, so will AVs bring to land transport. It is just more efficient and provides better customer service.
Really, alot of the light rail projects we see under construction are entirely unnecessary in the era of autonomous vehicles.
The same goes for commuter/regional rail and intercity rail. That is why I am against a project like HFR. If I am able to ride in an autonomous vehicle from Toronto to Ottawa, I will never ride the train again because it will have no advantages. I will be able to rest on the journey, get work done and probably arrive directly at my destination. It would also probably be cheaper because AV providers would have very few fixed costs. I could also see it being better for the environment as these AVs would overwhelming be electric whereas VIA will still be running diesel Siemens Chargers (that is if they weren't already shut down).
So do you expect everyone to take an AV from Keswick to Downtown Toronto? Sure the individual customer experience is better, but the negative externalities of a society completely reliant on autonomous vehicles are too great to bear. Urban sprawl for hundreds of kilometers in every direction. A blasted wasteland of parking garages and highways decimating our city centers. 20 Lane highways ploughing their way across all of Toronto.
If everyone thought like you, then where is the capacity on the roads to do that?
A single lane of highway can accommodate ~2000 vehicles per lane per hour in one direction. Let very generously say AV's double that. So 4000 vehicles per lane per hour in one direction. 12 Lanes of highway into Toronto (Thats the DVP, QEW, the Spadina Expressway and the Scarborough Expressway have also come to life). In total, that is 48000 people who can come into Toronto based on highway capacity at rush hour.
By contrast, with 15 minute headways, and assuming 2000 people per train, with 7 lines (LKE, Stouffville, Richmond Hill, Barrie, Kitchener, Milton, LKW), those alone provide the capacity for 56,000 people to come into Downtown Toronto by themselves per hour. In the case of GO expansion, there are going to be nearly 52 trains per hour at peak times coming into Union, meaning 104,000 people per hour will be served by those trains. To provide the equivalent highway service would mean constructing nearly 20 new lanes of highway heading into downtown.
Quite simply there isn't enough space in any major city for a majority of the population to abandon public transit and switch over to autonomous vehicles. And for the sake of our cities and urban areas, we cannot allow for your vision of an autonomous vehicle hell hole. Public transit is a necessity to ensure that future cities remain livable for humans. To prevent a Saudi/Dubai like future where highways sprawl everywhere and there is no possibility for a cohesive urban fabric.
Like this picture shows
So as long as humanity has to obey the laws of physics, there will continue to be a need for public transit.