I think the main reason for cultural differences, is that many artists don't travel. Not in the literal sense, rather that they are unknown outside there own country. When you get beyond Taylor Swift and Lady Gaga, how many artists are famous throughout the world.
Frankly, finding new artists is one reason I haunt this site and the music section in particular. Acts you might think everyone knows about, well you would be surprised. There are so many examples of great artists I have discovered, Shawn Colvin, Jason Isbell, the Milk Carton Kids and on and on.
As for British artists, I would think few of you will have heard of Kate Rusby, Martin Simpson, both of whom have graced the folk scene here for decades and I guarantee, you will love. Maybe I'm wrong and you do know them, but I doubt it.