I'm not from the UK so maybe I am mistaken but AFAIK the railways belong to the govt but they outsource the operation of them and of trains, stations etc. And if they limit operation times too (so that you get some certain amount of time then everybody bids), I think that is a good model.

This is how it works in Melbourne (actually, there is now a single company that runs the entire Metropolitan railway). Initially they split it into two companies each running half the city because competition. Because a train line on the east side of the city can compete with a train line on the west side. Now a single company runs both halves. I can't see how this is better than the government just running it.