The issue with privatisation for me is pretty simple. Despite record levels of taxation, the government don't appear to be responsible for anything anymore.

The private sector grift cycle seems to be

Win contract
Raise real terms prices
Lower real terms wages
Tell government you can't afford to deliver service
Receive subsidy
Cut back service anyway

It mostly applies to rail and having said that, I have actually been using the buses a fair bit since the price cap was introduced, good value because of the subsidy.

If you have a private sector bus network and two major parties who believe that is the only way then if the service is shit you have no recourse other than to not use it. The issue is that not everybody has that option, so you are left with the most vulnerable using a shit network, and because of the above, the buses won't be profitable and the public will end up subsidising anyway to keep routes running.

What we actually need is less people thinking they need a car to survive, more people using public transport = better public transport.