(American here) I knew a girl in college who was very sheltered: she was homeschooled in a rural setting by wealthy ultra-religious parents up until college. Her only outlet was british television. She's spoken with a badly formed british accent as long as I've known her.

I learned katakana as a middle schooler because I would wake up at 4am to watch anime on youtube on the family computer, so none of this surprises me.

Indoor kids can get weird :)

I didn't see any data in the article on this but I'm under the impression that we're making more indoor kids.