It's a stereotype with a grain of truth. In general, European tourists seem to be more accomplished or more enthusiastic hikers. You come across a lot of German-speaking people. But also Scandinavian and various others. Like all stereotypes, it breaks down on close inspection.
Yeah, I feel like any strenuous backcountry hike I take in the western U.S. will have me encounter at least one Scandinavian by its end.
Worldwide stereotype for off-beaten-track hikers. I remember Israelis felt over-represented on trails in South America too.