LPs only will operate these trains, but not from driver's cabin. They will operate (drive) the trains from control room. And speaking about efficiency, the automation gives them chance to run multiple trains at the same time.
Driverless cars will render a lot of car drivers jobless. But that issue is not for this forum. There aren't lot of LPs for one to become jobless. Matter of fact, there is scarcity of LPs as many prefer desk jobs over driving trains.