This is indeed interesting and also shows just how much room Democrats have to fall in the Upper Midwest and Northern Maine
It also illustrates that Pennsylvania doesn't have very much room left to swing rightwards when compared with the likes of Michigan, Wisconsin, and Iowa. While there's still places in Northeastern PA that can go further red, it isn't that large a portion of the state.
Southern Arkansas really stands out too, could we expect further Republican swings in the future around there?
Also eastern NC really stands out, and it's not just majority-black areas. There's still tons of room for Dems to fall there and not as much room to gain in the Triangle as you might expect.
On the other hand, there's probably still room for a lot of Dem growth in NOVA if you compare it to the densely populated parts of Maryland.