You dont need to rebuild the roads. This is a dead simple idea. You need sensors every x distances, and then use WiFi/mobile data to update cars of the model it should follow or rules of the road.

At this point though, you’ve started creating mass transit.

All good questions. IMO the government, cost benefit analysis needs to be conducted.

My perspective is inherently Dutch. I think the roads here get replaced quite often anyway.

While not sure of the value, I agree, a change at replacement time is essentially cost free.

Paving while laying RFID tag strips would cost nothing per mile, compared to the labour of pulling up and resurfacing.