If you had to listen to music exclusively from only one country, which one would you choose? And it can't be the US or UK.
I couldn't actually do that because I listen to too much music and limiting myself so extremely would drive me insane and I would grow very bored, very quickly.
However, many countries have great music, the problem is moreso that most countries only have a handful of really great, unique acts. So like it doesn't make sense to limit yourself to just one of them. You'll be much worse off than if you limited yourself to just the US or the UK.
Anyway, just based on sheer volume I would probably pick Germany or Japan (or just Canada since I live here).