Yeah, I was a bit glib. My impression is more specifically of the greater northwest vs rest. Perhaps just "the west" vs "the east".

Indiana drivers for example really do send it (in my experience). Which is not east coast of course.

There is a good bit of nuance... I would perhaps say more simply east of Mississippi vs west, but Texas varies by region and so-Cal drivers vary a lot as well, particularly compared to nor-Cal and central+eastern california. (I don't have an impression for nevada and new mexico drivers - I dont have any experience on country roads in those states)