More power to Seth and the breath of fresh air he brings to folk music. Much as I like folk music in most of its incarnations there is a hardcore of fundamentalist folkies (Arran jumper, personal pewter tankard, finger in ear) to whom anything new and different is anathema, frowned upon and dismissed as 'unauthentic'.
Folk music is, by its nature, organic; songs and tunes grow and mutate through interpretation over many years and anything new brought to the table should be applauded and encouraged if it adds to the rich variety of music we enjoy.
You can like it or dislike it according to personal taste but don't dismiss it just because it doesn't fit in with your perception of authenticity.