I tend to admire those "folk" musicians who have reached a certain level of competence & skill in their instrumental ( and vocal ) accomplishments . Examples that spring to mind are Martin Carthy, John Kirkpatrick, Martin Simpson,Nancy Kerr, to name just four from a long list of artistes whose playing I really admire and enjoy. I have always assumed that people like these have reached those levels as a result of first becoming interested in folk-music, and then taking up & learning to play,one or more of the instruments associated with that genre. BUT......!! I know,from personal expereience, that there are also many trained musicians who "discover" folk music at some point in their lives, and jolly good luck to them too, but they always sound, whatever they play, "too good " ,if you see what I mean ?? Their playing abilities are usually so good, that it almost sounds patronising ,in a way : I know they can"t help it, but they just don"t sound " ---Well, "right" !!