It's significantly an Anglosphere thing. Look at the recent world happiness survey and all the English-speaking countries are taking a nose dive in relative ranking versus other countries. Meanwhile world GDP is increasing.

I have a handful of idiosyncratic hypotheses, that I view as stacking on top of the more general cause of inflation and inequality:

- Western hegemony is weakening. Russia is attacking, China is gaining in strength, and many former backwaters are gaining ground. This creates uncertainty. In 1991, the US was the supreme undisputed hegemon.

- Global Social media is significantly English, and the US is the center of the now globalized culture wars, so there's no linguistic barriers to the resulting pathologies. The online world feels borderless and chaotic.

- There is now sectarian strife within English-speaking countries due to different moral tribes (some of those tribes being recent immigrants) living in the same country when there wasn't before. This is a new phenomenon in living memory in the Anglosphere.

- Russia and Iran are running cognitive warfare and other operations to destabilize social cohesion in the Anglosphere. Examples: (i) online - Gucifer, Internet Research Agency, (ii) real world - paying local gangsters to attack minorities.