Railways can be privatized if you keep the infrastructure (rails) public. Public railway infrastructure then charge the rail companies for usage of the rails. This should work in theory.
About affordable inter-city buslines, I feel that the new companies (uber like) that handle buses brought much more affordability than any law before.
What happens then is that you get lots of service between big cities, but smaller cities and towns lose service. Unless there are subsidies, prices will also increase.
In Germany at least, rail is viewed as a public good that should provide mobility to people in both big cities and more rural areas. Making it available outside the most heavily trafficked routes at a reasonable price is incompatible with privatization, again unless heavy subsidies are involved.
About affordable inter-city buslines, I feel that the new companies (uber like) that handle buses brought much more affordability than any law before.