Traditional singers are part of a process called anthropology. They are culture-based.
There are legitimate interpreters of this kind of singing regardless of where it comes from in the world. They are not necessarily members of the culture from which their songs emanate. The trouble with labeling is that contents inside the bottle may or may not reflect its true nature.

I think a problem arises when those who love folk music want to feel as though they are a part of the process when they sing and play these songs. Many will defend their "position" in the folk scheme of things.

The importance of preserving musical traditions and honoring them keeps musical imperialism by the music industry and popularizers from denying their value.

It's OK to feel a part of "the folk process" but it's not OK to dismiss the traditional performer who is culture-based and of interest to musicologists as characterized as being not important.

A true interest in folk music has to be equated with a willingness to accept that there are traditional performers who reflect the culture from which they emanate. A lot can be learned and enjoyed from relinquishing the denial that there is a folk tradition(s) in music.

At the same time, I believe that the interpreter of folk song be respected for their respective talents as well. Though when we speak of folk song, there is a well that we go to for inspiration and this is not the "revivalist" singer but someone who has grown up with a specific culture and has a depth of insight into it by virtue that they "are" that musical culture.

Folklorists and musicologists recognize the important heritage of culture-based traditional folk music. In some instances in is an endangered species but on the other side, it is still being done under the radar of the media, music biz, show biz etc.

The whole revival in England now serves as a problem in that there is arbitrary categories that may or may not be definitive in a scholarly sense. The argument on what is trad or not is usually based on individual opinions or preferences rather than musicological studies, anthropology or folklorist disciplines. I've been around the folk music scene for as long as anyone on this list. I've sung all kinds of songs but I know the difference between my reinterpretations of folk songs and the real traditional singers who come from their respective traditional sub-cultures.

Rock and Roll, Hip Hop, Singer/Songwriter and other categories are music business designations for recording bins and consumer demographics. When the disguise themselves as traditional folk music, they do a disservice to those who may not find voices in the entertainment business but say a lot of valuable things about their culture and nationality that won't be found elsewhere.