A lot of this is structural, but it's also entirely driven by the population and not just the politicians. There is a massive degrowth mentality going around for probably 20 years at this point, and many necessary projects are stuck behind citizens initiatives that are trying their best to kill them.
A good example of this is the Brenner-Nordzulauf, which is a proposed and necessary rail track that would connect to Italy via Austria. The tunnel on the Italian and Austrian side will be done in 2032, but the Germans are in a deadlock for many years now. At the moment they are talking that they won't start with their side of the project until after the tunnel is finished and they track won't be reality until 2040 or later. This is just one of many projects that are stuck with exactly the same issue all over Germany.
What makes all of this feel irreversible is because society at large started to push against the idea of GDP growth. I'm not even sure if politicians can "act now" if the problem is that the population is absolutely okay with how the country is running.
That there is what we calls democracy.
You cannot build anything in Germany for the government, as it will be delayed and changed endlessly. And you cannot build anything bigger, as competitors will sue the process, leading to endless delays and changes.
It's also called radical inefficiency.