That reminded me of this great quote: "The problem with defending the purity of the English language is that English is about as pure as a cribhouse whore. We don't just borrow words; on occasion, English has pursued other languages down alleyways to beat them unconscious and rifle their pockets for new vocabulary." -- James Nicoll
Except is generally does. That is still the primary definition in any common dictionary, and the understood meaning of this word.
In German we would say "Goethe captured the Zeitgeist of his epoch", on the other hand saying "Dark rimmed glass are in the Zeitgeist" would be strange.
I think the key is the understanding of "Blitz", which is associated with things like "fast" "hitting hard" "dangerous" "powerfull" "in a short amount of time" "to release a high amount of energy in a short amount of time" (and so on).
All of these words, formed like a tag cloud, are meshed into the the idea "Blitz" added to the german word for war ("Krieg").
If i think about the german language, its all about abstraction (and precision).
Waldläufer Himmelstürmer Götterdämmerung Doppelgänger Landstreicher Faulpelz Südseeplantagenbesitzer feine Pinkel Großkopferten Arschgeweih;
there could be hundred of those, invented, changed and transported through the centuries.
It's not just commonly "The Blitz", that's the only term used to describe that specific period of bombing.
If people use the word "Blitzkreig" in English, they're talking about the military strategy (usually only used in the context of WW2, but still).
In fact, The Blitz isn't really even an example of what would be referred to as Blitzkreig.
This has actually happened, for example Blitzkrieg (commonly the "blitz"); now this does not simply mean "lightning war", it very much references a particular part of a particular war. Also, Zeitgeist is used in English, but doesn't simply translate to "spirit of the time".
Often such compound words mean more than the sum of their parts (as I guess the OP kind of meant), which is what makes them interesting to other languages. OTOH, it seems pretty rare these constructs actually describe something that English doesn't have a word/phrase for already. In fact, I would say that its not so much that German has such constructs in their language that makes them interesting, and more that as a different culture they have different words to describe different concepts.
Edit: I should probably point out that I am a native English speaker that can speak fluently Norwegian. "Ohrwurm" and "Wunderkind" are such nonsense examples in this case; they are literal translations (just without the space, and are understandable from any Scandinavian language), and they are pretty much anti examples. Using foreign words that mean exactly the same as the English equivalents is nothing but pretentious, and doesn't support his central argument at all.