If there were enough of them and someone like Elon Musk with lots of eyes on the road via teslas could identify when the vehicles need human drivers (wrecks / construction / weather) then maybe the trucks approaching the human-need area could get off at one of the staging areas for a human to take over. It would help with the "human from beginning to end" problem that would require level 5 automation.
You might not even need to team up for eyes on the ground if you have lightweight drones regularly flying the routes back and forth.
One problem might be enough people to take over at a moments notice. Another problem might be drivers who only get periodic experience handling the truck. But it seems like a semi-feasible solution to get a step closer to highway freight automation.
Unfortunately, what the people paying for this want to achieve is the ability to not have to pay for a human driver, and if you need a human for the beginning and the end of the drive, you have to pay them for the whole time. So, while this would be an excellent application, I fear the business incentives are not aligned for it to happen first like it ought to.