Controlling trains is what I did from 1957 to 1993. That Uttoxeter box has a lot of white levers, indicating that they are out of service; lever not connected to anything. That's the way it was where I worked and I believe it's the same in the UK. If I understood correctly they don't have wayside signals on the high speed lines, only cab signals. If that's right, how do they handle it when the cab signals on the train fails? They thought of eliminating wayside signals on the Pennsy, where I worked, but didn't do it; kept both kind of signals.
The video says that they only have four signal aspects. The Pennsy needed more than that. From "Signal Aspects from the Rule Books - Railroad Signals of the US." Note that the chart shows cab signals, small. It doesn't show all Pennsy signals, semaphores or color light signals used in Penn Station, New York, for instance.