What would you prefer? A switch, a relay, an actuator and a bit of
wire? Why be complicated if a simple mechanism works?

You could say the same about the rest of the train control
systems. Camshafts worked , so why bother using solid state
electronics? Why bother having in cab video when the driver
is quite capable of sticking his head out the window and looking down
the platform (tho obviously this would mean
him getting off his arse for a non tea/toilet related event so its
probably banned by union rules).

B2003