Your bafflement is wide widely experienced. The lack of any easy to understand reason makes it very difficult to discuss. As a result we live with growing anxiety and confusion.
I think the primary reason for this aberrant behavior is the pathological result of uncontrolled economic destruction of a previously more egalitarian culture. Extreme class imbalance had been normal from the rise cities and kingdoms, i.e. Civilization, but the rise of technology, science, market economics and a growing middle class made that old and unacceptable.
Unfortunately the failure to continuously correct for the structural problems of capitalism by allowing greed to rule produced full predatory capitalism by the late 20th century. This is an inherently unstable system running out of control and consuming itself. See Picketty.
When material wealth and greed are the only virtues and almost all the wealth is in the hands of a tiny elite a further reversal takes place. Just as capitalism ceases to produce new unique goods because interest returns on capital are better and easier, the model for success becomes exploration and denial.
At the top the elite is concerned with maintaining dominance in the artificial zero sun game. Their wealth grows without effort so oppressing others becomes the status activity.
The newly oppressed are angry but with no idea why what had made their parents successful no longer works. That converges with the desire to deny and oppress among the problem elite. The game becomes turning people on each other which also protects the elite.
The economy is now a zero sum rigged lottery with growing pathology based on layers of lies. That leads to the endless denunciation of social democratic systems because, somehow, guaranteing everyone living in an equitable society will mean that the angry and oppressed will have less.
A key cultural component of this is the provincialism of Trumpistan that is also opioid country. Forty years of growing racism and misinformation about the rest of the planet combined with the memory that their parents were part of the richest and most advanced country in history was used to to make them frightened of all they could lose.
But that is all gone. And soon the lies will die in the climate crisis when the rules of living change.