SW, a former ambassador to Austria seems to have latched on to this term.  However, she ignores the fact that German speaking countries such Austria and Germany are economic powerhouses of Europe and they have tons of jobs and wealth created by industry and inventors.  Even more so Switzerland has tons of wealth.  Meanwhile, over in Romania, Bulgaria, and to a lesser extent Czechs, they have a lot of broke folks who have poor work ethic, and many in Romania want to scam or hack online for money.

So it is not really a matter of trafficking it is more of the ethnic makeup of German speaking countries being superior to lazy Slavic based countries such that they have higher wealth and better employment.  The hottest chicks leave the Slavic world and try to get into the German speaking countries.  Not really having anything to do with trafficking, just normal movement.