I rather think Jams may have been the band I was referring to above which I heard at Sidmouth and liked.

I get suspicious when I heard things said like "there is no great tradition " - because that is just the kind of thing which people used to say about folk song in England once upon a time. And they'd then go on to say "in contrast to Germany" and things like that.

Maybe it's true that "most of us Germans likes doing things well organized," though there are a lot of Germans who are far from being like that. But musical traditions tend on the whole to be retained and passed on by people who aren't most people.

It may be of course that all the upheavals have wiped all and twisted many kinds of traditional music in Germany itself. But there must have been musical traditions carried on in expatriate communities, for example in America or in the further reaches of Russia. And not just oompah stuff.