If I sing "in the pines", I don't sing it as "black girl, black girl, where have you been?", I sing it as "little girl, little girl, where have you been?" for the obvious reason that I'm white in a still-racist society. It helps that lots of bluegrass (rather than blues) versions of the song sing this anyway.

To my mind, any white person who considered using the word "black" (pace Leadbelly's "Black Girl") on the basis that they were "telling a story" or "playing a part" is socially and politically naive, living in a bubble.