I am not an expert in music from Scandinavia but anyone notice that the popular music from there lies in extremes. One is death metal/hardcore rock bands like In Flames etc and on the other hand really relaxing experimental bands like Sigur Ros, Mum etc.
What are your thoughts in this regard?

I think, you can't even generalize Scandinavia. The differences between e.g. Iceland and Sweden are huge.

I didn't even know Iceland counted as Scandinavia.