Testing is going on now and the eta is abot 2030. I used to think we can't take care of existing roads either - until I moved more south without six months of snow and salt. For most of the county, constant repaving is not necessary and road work can be done year round - Unlike in the northeast.Maybe its possible one day. I hate to say never.
Hell Elon designed a rocket that can launch into outer space and then land on a wirelessly controlled barge in the middle of the ocean.
Currently though we are not there. Hell we can't even take care of our existing roadways, let alone putting electricity in them