Yea they could put down visual markers on the road to make it easier for CV or ML models to be trained against, or maybe even physical tracks to mechanically guide these cars so that minimal software is needed. Multiple cars can be linked together for efficiency.

Yeah I think if car manufacturers can come together on standards for signs... And even maybe signs that send RF signals to cars to give them hints of what is nearby it could go a long way. Instead of pretending like the only way is to make cars work with our human friendly system.

A car that can drive itself in a specifically prepared environment would hardly qualify as "fully self driving". You could achieve that with all the AI prowess of a mechanical connection between the steering linkage and some guide rails. And you'd still fail to get even the tiniest development budget for a car that won't sell anywhere else.

If you'd build a genuinely smart city completely from scratch, the most elegant way would be to completely remove the need for own cars. But that's obviously not going to happen when its a project designed and financed by an automaker.

It is when you sell them the autonomous cars that people can use and maintain them with the guarantee that they wont breakdown often when used basically.