I discovered the pendulum of social movements after reading Bertrand Russell's "The Ancestry of Fascism" at a relative young age (~16 years old), it only really made sense after my 30s though.

It required me watching, experiencing how things I had considered settled and humanity was over them started to turn back: the rise of fascistic tendencies in different societies, anti-intellectualism, etc. things that as a teenager/young adult I never considered could become societal issues again.