Even the local news people seem to have lost their twang.
It's not only in the South. In major market radio you are told, lose the heavy accent or lose the job. Regional sport-casters, when it comes to accents are a whole different ball game.
The radio & even TV sports related CEO's overlook the accents since it draws in the local listeners, thus they will hear the local commercials, and that's what sells in a sports 'local' & also 'rural' sports markets, and to a degree 'very local' talk show markets in mostly rural listening zones.