How did bluegrass become the new sound of political protest across the US

Bluegrass music has been considered unworthy of notice: low art, uncomfortably associated with white redneck culture, but now the things are changing - this music is becoming increasingly politically potent, because of it "fundamentally social tradition – and the democracy of the picking circle", as the Guardian points out - "bluegrass is unique in the wider culture war: a rare public space where both sides of the great American divide can and will sit down together. The passion and pride that bluegrassers feel for their music override political, and even personal, animosity, forging unlikely friendships, challenging innate prejudices".