Charley Pride was always a country musician. Maybe a better comparison would be Lionel Richie or The Pointer Sisters, who made their name in other genres, then dabbled in country.
Or Ronnie Milsap. His first hit was on the soul chart, and much later he was big in country.
My point was that country singers have been black as well as white. Regardless of what genre someone made their name in, it doesn't deny them the right to present a country music song. It will be judged upon how it is received, period.
Country music has already changed by the white artists who have basically made it into another form of rock, country rock.
Music genres goes where its fans allow it to go.