Well, the EU insists that track & train operations are separate. (ironically the UK _is_ combining passenger operations and track somewhat back together, which is only possible because of brexit).

The bigger issue tbh is the enormous cost inflation in civil engineering in general. This seems to be a problem everywhere. There's no doubt some of this is caused by material cost increases, labour shortages etc, but I'd say the huge amounts of regulation added over the years is really a core driver of this.

No. They cut on maintenance to make line go up. And then they deconstructed existing switches, signal boxes, train lines, and train stations to cut costs even more. This is not an EU problem or a regulations problem or labour cost problem. These are the fruits of privatisation and capitalism.