Why, precisely, would the failure of The Marvels make you chuckle? Ms Marvel was fantastic and Iman Vellani is the most charismatic actor the MCU has had since Robert Downey Jr. It may well underperform, but I'm not sure why that would bring any well adjusted person joy.
And the culture war is "real" to the extent that it is having a real impact on many individuals and institutions. There has been a very significant shift in the nation's political rhetoric since about 2012. You're quite correct that, to fully understand what is happening, one needs to have a firm grasp on American history, but I suspect the lessons you and I draw from that history might be quite different.