I haven't written anything about being a blues artist being contingent on age; Robert Johnson was a blues artist, I think and I bet you think.

Who decides whether McAbee was a blues artist would be e.g. Robert Dixon and John Godrich, who included him in the 1982 edition of their famous reference work and wrote there that he "certainly sounds black." He was white. What Dixon was thinking about in recent years (he's 79), and admitted he hadn't thought about back then, was that trying to eliminate people from a book on the basis of them not being black was, in the real world, a _different_, inconsistent approach from noticing what they sounded like. How Dixon honestly thought McAbee sounded illustrates the inconsistency.