Well, the most immediate contextual change is the setting itself: from Spain to the United States. Both have diverse terrains, but the connected-ness of the USA (via highways/interstates) would allow for a differently paced story. Additionally, the "resurrection of chivalry" would be replaced with some other revival movement to a "simpler time" and its ethics. To be fair, that notion is already prevalent among many conservatives and anti-progressives. The discourses between new Quixote and Panza would likely be as fire-y as recent Presidential debates, stoked in populist ideals and failed promises from those recent agents of change to society as a whole. Overall, it would be an interesting take on an old classic, and likely prompt serious discussion about our romanticizing of the past.