That's a very good argument for restricting the folk label.

Folk can only be an observable phenomenon defined by what it is, rather than what people thought it might have once been back in 1954 (and even then were several light-years wide of the mark). In my lifetime Folk has been everything from the Traditional Northumbrian Pipe Music of Billy Pigg to the Free-Form South African Jazz of Johnny Mbizo Dyani who frequently spoke of his music as being Folk. I think of everything I do as being Folk - be it This or This. No good can ever come out restricting anything, on the contrary, the wider our appreciations of Folk the better it will be.