I've discovered that Scandinavian heavy metal is exponentially bigger in Germany than anywhere in Scandinavia, so it gives a skewed impression. I think some of those bands troll their German fans too. A German friend of mine once asked me to translate some songs from one of her favourite bands. I swear the bellicose roaring consisted of variants of "forest, forest, forest, treeeeeeees!" While another was something like "rocks, rocks, fog, elves!" I think I ruined it for her. Incidentally, it's easier to get ahold of real traditional folk music, recoded in Scandinavia, by Scandinavians who were brought up in the tradition abroad. Many of those musicians are only known in other genres such as jazz and, shudder, schlager in Scandinavia.