+1 high speed should only be enabled by multiple redundant safety system being operational. Otherwise, it needs to operate at line of sight speeds.

It's not a suggestion, it is an order and a movement authority. That would have been nice, but the drivers are not required to make such a decision. The moment you issue a movement authority, you must assume the train operates with the max speed and distance of it immediately, and that must be safe. Train drivers do not decide for the speed and trajectory a train is going to take. They are responsible for that their train drives safely inside the movement authorities given to them, they are not able and hence not responsible to ensure the safety of the network. They are more equivalent to a car mechanic, not to a car driver.