The real brain melter was the societal culture shift.
I grew up witnessing "the end of history" with my own eyes. People were getting wiser and kinder year after year, decade after decade. It was like a feedback loop of positive changes, the only way was up.
Then 2010s hit and I'm still processing the 180 degrees shift. I read dozens of books about nazis, authoritarianism, societal memory, cults, fucking roman empire. But I still have cognitive dissonance every time I open news feed.