Self driving is going the way of fusion power. Always just a couple years away. I still believe divided highway trucking between major cities with last mile handoff to humans has legs, but I wonder how much the Tesla claims have poisoned the proverbial well of a more constrained system for the foreseeable future.
That just seems like a train to be honest, and runs into the same problems of who is going to pay for the infrastructure and handle priority.
I don't think divided lanes are required either. The problems with self-driving trucking aren't about following the lane.