German trains were great twenty years ago. I wouldn't be surprised if things went haywire after lockdown. Many things did. It gave people a licence not to work and introduced a sloppiness into everything.
I'm fairly certain it was before that, as someone living in The Netherlands we'd always get warned to make sure there was at least 30-60 minute transit time between each stop in Germany when travelling international, as the expectation was that the train would be (extremely) late.
While it is true that that many problems where already visible 10 years ago, it is also true tat during the pandemic more trains were on time because having very few passengers speeds up the boarding/offboarding at stations enormously. So the pandemic somehow delayed the already inevitable fall into the abyss.
