BBS. Since no-one else appears to have mentioned it, far from being a success (minor or otherwise) in the 1920s, Robert Johnson did not record until 1936; a fact you would have picked up on if you'd bothered to listen to him ast all closely.

As for your attack on Leadbelly. Anyone can tear an artist to pieces with a few badly chosen adjectives, as you chose to do. The trouble is they just don't mean anything.