I experienced a less subtle version of that with my usage of "howdy".

Context: I wasn't born in the US, but was only 4 when we immigrated. For whatever reason young me gravitated toward "howdy" as my greeting. Probably just my young love of westerns; regardless, "howdy" has always been my informal "yo".

Anyway, my first few months in the South, local would ask me if I was making fun of them when I said "Howdy all" / "Howdy guys." Same way I've always said it. Now it was rare, but I would hear locals say "howdy" on occasion without ridicule. Something about my saying it caught a weary eye.

When I'm down South now, I just say "Hi". Weirdly, no one else has ever mentioned it.