I would imagine they're referring to cultural and behavioral homogeneity, not necessarily national or distinctly ethnic homogeneity.

I'm sorry that you have to be around Germans, Austrians, Italians, Spaniards, and—worst of all—the French. Nobody should ever go through that.

There are 150 nationalities in Zurich.

They are also the cream of the crop from their respective nations. Diplomats and bankers.

This is such a fine sarcasm, chef's kiss!

Imagine implying that Swiss Germans and German Germans look upon each other with familiarity instead of wariness or even suspicion.

Wait til they hear about East German Germans and West German Germans.