On Sat, 29 Jul 2017 20:58:30 -0400, Keyser Soze
wrote:

"Hillbilly" music is an apt if socially incorrect descriptor for
bluegrass music.

Wiki, for example, offers the following:

Isn't it a slippery slope to use a cultural slur to describe music?
At that point isn't salsa "beaner" music
Would Show tunes be "queer" music?
Asian tunes "chink" music?
I hesitate to say what we would have to call rap.