The blues has roots in blue grass too, which is white people music dating all the way back to hymns being sung on pirate ships and soldiers during various wars. Look into 'House of the rising Sun' for example.
People who try to claim it is straight up black music are flat out wrong.
Blue grass is derived from West African folk music, nothing white about that. Just another appropriated form of black music.
The only white man who gets a pass is Stevie Ray Vaughan. Blues is black people's music, keep it that way.