It draws a lot on Losurdo’s book on Nietzsche, and looks at the history of the 20th century from a philosophical lens where Marx lays the foundation of internationalist, anti-fascist struggle, while Nietzsche is the philosopher whose ideas are the foundations of fascism itself. It argues that Nietzsche provides a very strong alternative to Marxism for the ruling class, a model for maintaining power and rank order for eternity, as opposed to Marxist dialectics which hold that history is in motion and nothing is eternal. Then if you look at the category of “Aristocratic Marxism” as referring to Marxists that absorbed an unhealthy amount of influence from Nietzsche’s aristocratic, austere, and anti-egalitarian thought, the OP is basically elaborating some more specific criticisms of that category. I think in practical terms, the category of “Aristocratic Marxists” intersects a lot with what Losurdo would call Western Marxists (though it’s not a complete overlap).

I’m not familiar with Spinoza or criticism of Spinoza so I can’t really comment on that side of the OP.