I know quite a lot of railway history. So I can tell you this - most of the old private companies never made a bean. (They survived because, oddly, there was a concept of public service that is quite extinct today, certainly in the private sector.) Dividends were often low or non-existent for decades. The Cambrian Railways, serving much of rural Wales, is a good example. Run on a shoestring with antique rolling stock, it was never going to make anyone rich. The people behind it were largely bigwigs with a concept of noblesse oblige. They ran the railway chiefly for the public good, although most of them had interests in Wales, such as landowning, so they benefited indirectly.
As statutory companies, they did not go bankrupt. The very worst that could happen was they were put into receivership under the supervision of the courts, either until someone took them over or they somehow managed to square the books and exit this status.
This was in the glory days before WWI when there was no effective competition unless you count the carrier's cart and coastal shipping. Everything went by rail, from newspapers to elephants.
The railways that did make money were few and far between. What they had in common was heavy goods and mineral traffic. The North Eastern, with a virtual monopoly of what was a very prosperous area at the time, was an example of a large, profitable company. The Taff Vale, which mainly existed to take coal to Cardiff Docks, is an example of a small one.
In all cases, passenger traffic was the icing on the cake, not the cake.
World War One effectively fucked this model. Our coal export business died for a start. Then, after the war, every Tom, Dick and Harry bought a war surplus lorry and started a road haulage business. From that, the present road haulage industry grew.
In short, the railways gradually lost all their most profitable traffic. It's a bit of an exaggeration to say that they were all basket cases by the end of WW2, but only a bit. The war and its aftermath propped them up for a while, but cheap oil and petrol soon ended that.
Anyway, with very rare exceptions, passenger traffic just is not profitable. Commuter traffic, which requires stock to sit in sidings for much of the day doing nowt, is particularly unremunerative.
The cold truth is that for national, social and political reasons, the railways need to be subsidised. And our train fares are less subsidised than most in Europe which is why the fares are so stupidly high.
Now, given that you are going to subsidise the service - or certainly the great majority of it - is there any advantage in giving that public money to private companies when we could give it to an industry that we own?
Privatisation has led to the ludicrous situation where one company runs the trains, another leases out the rolling stock, and a third (owned by the state!) provides the infrastructure. This is instead of an integrated structure! The inefficiencies should be obvious.
It also leads to the absurdity that the three trains an hour from Manchester to Sheffield are run by three different companies, with all the cheap tickets only valid on one. You have to pay more if you want to just travel on any train. How is that sane? It's more like something out of Alice in Wonderland. Under BR, with very rare exceptions, your ticket, however cheap, was valid by any train. You did not have to look at the livery of the coaches to work out whether you were allowed on.
inv.vern.cc
en.wikipedia.org