I'm not gonna say the claims used to be true, but at least they used to be much closer to truth then than today. And I've long felt that having these kind of national beliefs can cause people/voters to neglect those things - e.g. all the bad claims about education can be just brushed off with "well we have the best education here so no worries!" - and few decades later they're not even close to true anymore.
Reminds me of a saying in poker, when many good players changed their style radically when playing against worse players and started playing way too bad starting hands (thinking they can just outplay them on the later betting rounds), something to the effect "It isn't enough that you know how to play better than your opponents, you have to actually do it"
I've heard it said that the idea that Germans are efficient is a myth. (The new Berlin airport is one example.)
Germans are, rather, *rule followers*.
I wouldn't say this either. Many people in Germany do care about efficiency, but they have nearly completely resignated about systemic problems where they can change nothing.