> The rise of fascism...was a black swan event

This is a very bold claim, and many (including myself) argue that authoritarianism and many things identified fascist are the inevitable result of liberal democracy. Capitalism cannibalizing itself, etc etc, which again many would argue is also inevitable. Marx outlines the inevitable decline of profit that drives this phenomenon in Volume III of Capital, but it is also a viewpoint shared by Adam Smith himself, John Stuart Mills, etc etc. Schumpeter also relies on it heavily in his analysis of the role of private property in driving market processes.

As profits inevitably decline, either capital will inevitably seize control of the state (dictatorship of capital) or the people do (dictatorship of the proletariat). Their interests are inherently at odds, and market forces ensures that this contradiction must be resolved. Inevitably.