If one's position and circle is below the class threshold that cares for these things, such a stigma would be invisible - it just wouldn't be a thing that they'd have seen in their lived experience.
And, here's the hook to what you say regarding it being a regional thing: this class distinctions are also applied at the regional level. E.g. whole states can be considered "lower social class" (regardless if they have millionaires or well off upper middle class people and so on).
In "high class" states or circles within a state, though, the stigma would a quite real thing (even if it's just an inconsequental matter, as seen from outside).
It's not about wealth levels either, as class concerns are just as high in stressed-to-appear-appropriately-high-class aspiring classes, that make less than what a developer does, but their circles are all about class distinctions and their shibboleths. The stereotypical "New Yorker" reader would be a total weirdo about such matters, even more stressed and awkward about following all the BS rules than people actually belonging to the 0.1%.
But even if you are a billionaire, you can be the low-class butt of the joke to "old money" types.
(That's my understanding of the US class system on this matter - there are some quite good books about it, "Class" by Paul Fussell is quite good. It's also a subject that certain kinds of literature and journalism wont shut up about).