People are generally unhappy and realize things are bad, which results in political radicalization. That generally goes one of two ways: recognizing that the billionaires who run society are the problem and that they must be eliminated, or nazism. Fascist billionaires like Elon Musk or Peter Thiel see this and go “holy shit we need to make sure those people become nazis and don’t want to kill us”, which results in nazi propaganda being openly spread on capitalist-owned social media sites, which is the majority of the internet.

There are other factors, like most in the west perceiving of their class as being petit-bourgeois, even when they own no capital, and as we know the petit-bourgeois were one of the largest supporters of nazism.