The fragmented nature of modern-day railways

We start a project a day, with a certain set of needs and desires. The project takes time to be complete, let's say 10-15-20 years, at the end some parts of the network are still useful and valuable many others are not. Change them is hard, demand again more time, once done (IF done) we end up in the similar departure scenario.

Society does not change that fast in general, but still do. In the past we have followed nature and people have started to follow transport networks, now with climate change, transport tech changes etc we experience issues.

The sole solution is IMO:

- do their best to create free networks, like privileging air and water transports who demand infra but only at their endpoints letting paths evolve much faster and simpler;

- do their best to avoid LARGE infra, preferring capillar ones were surely there would be useless parts but being a small local size and much connected network any segment cost far less so both profitable ones and unprofitable ones can be operated.

In the past we have seen something like this, for rails for instance: http://carfree.fr/img/2015/06/sncf.jpg overall the old network worked LESS well and cost A BIT more, but the old one allow many paths from A to B so allow flexibility, the new one is far more efficient AS LONG AS transportation needs do not change.

We have seen the very same issue in modern just-in-time manufacturing and we see that solutions found so far are the same: less efficiency traded for more flexibility.

If you need to move cargo from one train to another, just do it somewhere away from the main tracks.

"different signaling systems, different voltages for electrical trains" isn't that much of a problem nowadays. There are almost always enough multi-system engines available that can cross borders and cope with those changes. We have a jumble of voltages in Czechia and yet another voltage on our German/Austrian borders, and trains go through without a hitch, not even slowing down, full speed.

A break of gauge is a different beast: a real tough problem. Even the railcars are wider on wide-gauge railways, which means that they cannot pass through some European tunnels etc.

Frankly, the only solution is to re-gauge the entire Ukraine to 1435 mm and introduce a new fleet of railway vehicles there. As an added bonus, that would complicate further Russian invasions in the future, as the Russian army still heavily relies on rail for its logistics.

This will be expensive, but the EU could pay for that, plus a lot of that work could be done by European contractors.

We're only going to need more capacity for climate-friendly transportation of both passengers and freight, and stronger tracks and couplers for heavier trains is going to help with efficiency of the latter.