I think a lot of the US success was powered by little kids. Last summer I was a counselor for a bunch of first graders at a camp and they were obsessed with it because they're, like, actually 7 years old. I've never met a single older kid or adult openly into it around here.
They loved Hello too, though. Still lowkey proud my group won Olympic week for our rendition of Hello ("from the Jedi, do or do not there is no try")