AFAIK to fix reliability no new major infrastructure projects would be required (at least for most of the reliability offenses). They would just need to maintain/modernize existing infrastructure and rolling stock, so all things that aren't really opposable.
To achieve the Deutschlandtakt as noted in the article, yes new infrastructure projects are required, but I think most people would be happy with all the existing service running as well as it has ~15-20 years ago.
