Your query takes me back. In the 1960's I had a friend from Lexington, Kentucky who was a Leon Bibb fan. I listened to his music and liked it, especially a lovely song called "Adieu Madras." I still sing snatches of it from time to time.

We didn't think of Leon Bibb as being part of any so-called folk revival. We just thought of him as a gentle person who sang enjoyable songs. At that distant time, enjoyable songs were still occasionally permitted on commercial radio.

I think terms like "folk revival" and "Celtic fringe" represent the viewpoint of uninformed people in LA and Nashville who don't know that traditional never really dies.