The thrust of steve_gh's argument seemed to be that decentralisation of that (publicly owned, as you are noting) body, and particularly alignment with the train operating company regions, would improve the situation.

I wanted to get their views on any industry-specific constraints around the orthogonality of "centralisation" and "ownership", because I feel like they are too frequently conflated (not by anyone in this thread, to be clear), despite not being inherently linked - but there might be some good reasons for that in the context of the current state of the British railway network.