Just something MAGA-people seem to have a hard time with sometimes. Probably not as much when Americans are speaking to themselves, but as a non-American, sometimes it’s challenging to get “those people” to admit that there is indeed anything wrong with the US. As in they won’t accept a single criticism, and will loudly proclaim “America is the greatest country in the world”, while wearing a “Make America Great Again” hat, which for me pretty explicitly means America isn’t great, if it has to be made to be such again.
I think the reason why it’s so pervasive is that it taps into the romantic notion that things were better in the good old days, and people can overlay whatever meaning they wish.
The reality is that in the grand scheme of things, the world does get better over time. Most of human history consists of wars, plagues, famines, power struggles, authoritarian rule.
But occasionally some aspects of the world get worse, too. For example, the widespread introduction of cars was “human progress” in the sense of enabling everyone to be mobile; it led to environmental problems and degradation of quality of life for many people.