That all may be true and right, but looks and sounds so abstract. Since a picture says more than thousand words, I'll leave some here, of the same point, right at the border between the Netherlands and Germany:
https://openstreetmap.de/karte/?zoom=17&lat=51.90181&lon=6.1...
https://maps.app.goo.gl/Ynqa5V8YAZgiqdoJ6
https://www.bing.com/maps?cp=51.901264%7E6.137596&lvl=18.7&s...
What do they have in common?
On the Dutch side 3 modern tracks, fully operational.
One of them ending abruptly at a buffer stop.
Why?
Because the German side has only two old tracks.
This is going on for slightly more than a decade, IIRC.
So it could be said that Germany is putting the Dutch investment on the "Abstellgleis", because...why not?
Same shit is going on at the https://de.wikipedia.org/wiki/Brenner-Nordzulauf#Stand_auf_d... for the https://de.wikipedia.org/wiki/Brennerbasistunnel
Als möglicher Termin für einen Baubeginn in Deutschland wird der Anfang der 2030er Jahre genannt, für eine Fertigstellung 2040.
WIE BITTE?!
Two smaller countries, doing massive rail infrastructure projects, 'can do' mostly on time and budget.
Why can't Germany?
Hmmhrrrhmm. What else comes to mind? Oh yes! The https://de.wikipedia.org/wiki/Fehmarnbelttunnel
Germany zero points again. Denmark more, wins! Or not. Because of what use is a bridge, err... tunnel to nowhere, for more years than necessary?