There's a difference between the trolley speeding towards someone tied to the tracks, versus someone tied to the tracks but the trolley is stationary, and to someone standing at the station looking at the bare ground and saying "if we built some tracks and put a trolley on it, and then tied someone to the tracks the trolley would kill them! We need to regulate against this dangerous trolley technology before it's too late". Then instead someone builds a freeway because it turns out the area wasn't well suited to a rail trolley.