There's no reason to force drivers in the straight, open-ended highways of the Southwest to do 55. Even on the NYS Thruway that's a snail's pace. Sixty-five seems reasonable to me, though on some of those roads 70 or 75 appears slow at times.
Not to the people who live in the Catskills, Apparently they haven't got word of the change of the speed limit and continue to blissfully plod along at 55 mph, even in the left lane with nobody in front of them.