the Entertainment INDUSTRY....is at the root of this.
Tv and Movies....used a recognizable style of speech....as a “gag” several decades ago.....and it stuck in the “minds” of many.
Did you see the movie Shadrach, with Harvey Keitel cast as a poor southern moonshiner in Virginia in the Depression?
Somebody was nuts to cast him in that role. Andie MacDowell, his co-star is from North Carolina, so her accent was real, if a little bit strained at times.....................