I think you only perceive “incongruence” because of internalized biases you hold. With respect to other examples, listen to recordings of NASA flight control,

I think you only perceive “incongruence” because of internalized biases you hold. With respect to other examples, listen to recordings of NASA flight control, especially from the early days of the Space program. I acknowledge that a lot of what you will hear is Texan and not strictly “Southern,” although that itself can be broken down regionally as well. Recordings of engineers at Huntsville US Space and Rocket center also feature Alabaman and other Southern accents.