I think this is broadly correct and comes from the social media nationalization of politics / news. R dominance in the South has rested on southern white voters being much more Republican than national avg white voters. Midwest swinginess relied on them being much less Republican than national avg.
People get mad at me when I say it seems like there are forces now pulling the Deep South towards Dems while the upper Midwest has looked relatively weaker for them in what’s looking like a big national blue shift, but I don’t know how you can’t at least be open to it.