Personally I'd restrict "super" status to a lot less than 20% or 30% of the population - certainly that's what the NYT article is doing. Fluency in two languages is pretty much a requirement for any but the most basic professional positions in much of Europe, and I wouldn't want to start calling every middle-level manager or accounts person "super."

I live in Switzerland, most people I know speak at minimum three languages fluently, and a huge proportion 4 or 5.