Earlier quoted context omitted.
I'm unclear what your argument is here. Having rail be so expensive or badly run that people decide to use roads instead doesn't seem like a win for privatisation. Encouraging people onto roads or even flying is also a disaster for tackling climate change.
Since privatisation in 1994 to pre-covid 2019, rail usage increased from 36 billion km to 80 billion km, more than doubling. Road increased from 666 to 741 bkm, increasing 11%.
In theory this extra cash and economies of scale should have been an ideal situation whereby rail transport could be significantly improved. In practice we've seen above-inflation fare rises and (in my experience) dreadful services.