Earlier quoted context omitted.
Is it fair to say they are "beta testing" on public roads with the public paying the price after they've done four years with a supervised driver in the cab?
Sure .. if by "beta testing" you acknowledge a decade of driverless 100 tonne+ trucks operating in large fleets on private mining sites mixed in with "regular" driver vehicles. This might be the first foray onto a subset of open public roads but it's not the first serious use of semi autonomous trucks mixed in with human traffic.
They usually map out the site and show you which roads you can take in your vehicle and they are completely separate from the operations roads. There are only intersections and it's always the responsibility of passenger cars to come to a complete stop and wait for any cross traffic to pass before proceeding.
I remember this well because we had a job servicing specific equipment on a particular mining companies sites in northern Minnesota. One time we drove on the wrong road. A security vehicle saw us and drove up on us at an extremely high rate of speed to clear us off the truck road and onto the proper passenger road. He spent a good few minutes yelling at us once we were clear. People have been killed this way.