A course on recognizing bias against lowland Southerners would be funny but not wrong or inappropriate and you'd see plenty of rich coastal fragility on display.
Classism and regionalism are absolutely huge in this country, especially when those on the receiving end are not in a racial minority.
But what would people do if there were no easily identifiable out groups to stereotype and mock?
At a past job, I worked for a company headquartered on the upper east coast, but which had opened a "tech hub" in the mid-sized Southern city where I lived at the time. Some of my co-workers had fairly pronounced Southern accents and people in the home office would regularly laugh and make fun of them during meetings. And after I put in my notice, the tech lead on the project I was on declared, completely unprompted, during a completely unrelated call that "we haven't had any issues with code quality or anything, but Southerners are just slow. That's just how they are. It's the culture." I think that I will regret for the rest of my life not telling him to go eff himself right then and there.
And I wish I could say that that was an exception to my experience elsewhere, but while living on the east coast I heard more offhand comments about "stupid Southerners" than I can count, often followed by an awkward "I mean, not you of course, you're different". Interestingly, many (but not all) of the same people who think it's funny to beat up on the South are also the most likely to make impassioned performative declarations of support for every DEI initiative they come across. The level of cognitive dissonance required to maintain that kind of mindset must be intense.
Holding and advancing multiple deeply contradictory ideas is something humans are very good at.
I've come to believe that most people spend very little time asking if their ideas are reasonable. They just believe what they need to believe to fit into a group. It's more about group membership signaling than anything else.
Primates will choose social connection over food, so it's not surprising that we'll also choose social connection over rationality.
> On October 26, 1909, the Rockefeller Sanitary Commission for the Eradication of Hookworm Disease was organized as a result of a gift of US$1 million from John D. Rockefeller, Sr. The five-year program was a remarkable success and a great contribution to the United States' public health, instilling public education, medication, field work and modern government health departments in eleven southern states.[45] The hookworm exhibit was a prominent part of the 1910 Mississippi state fair.
> The commission found that an average of 40% of school-aged children were infected with hookworm.
https://en.wikipedia.org/wiki/Hookworm_infestation#Eradicati...
The South gets it the worst. When I was in college (University of Cincinnati) engineering students from the South were sometimes encouraged to lose their Southern accents because it made them sound "stupid." I heard a few stories about this.