When on a plane there's a "Ground" alert, pilot is supposed to act immediately to prevent a crash. He cannot be absent from the cabin and he cannot finish the game level on his smartphone first. The same is with the car, that is not sold as fully autonomous: if you are on the driver seat, you are responsible for making the final decisions on steering and braking, not a technology. Technology may help you and prevent from making mistakes, but it was not promised or advertised that it will help in 100% of the cases.
As we see in latest Tesla report, there were multiple warnings to which the driver should respond: this means, that the problem was detected with enough time to react and the autopilot was not able to solve it on its own. Thus, it does not make sense to blame the autopilot - the technology did behave as expected (when problem cannot be solved, report asap to the owner, that he should intervene).
What Tesla can actually be blamed for, is the misunderstanding of the autopilot capabilities by the drivers. It's not an algorithmic bug, but rather a usability one. Perhaps, the warning should be issued earlier or in a more clear way. Perhaps, the drivers should receive some training, to act as supervisors of the system, not as passengers, or there even should exist a special driving license for such types of cars.
Nevertheless, the main fault was not the driver's and not the Tesla's. The safety of this road should be guaranteed by the authorities in charge, the navigation should be made sufficient for the drivers, and they clearly failed to do so.