Marx was an economic determinist. He argued that a nation’s political system and culture were driven by its economic system, which was defined by the type and ownership of the means of production. A capitalist society, characterized by large manufacturing companies with middle class owners, would thus have a political system run for the benefit of the middle class. And so on.
The irony of the Chinese system is that the political “superstructure” is thoroughly communist, but the economy is predominantly capitalist. A genuine Marxist would say that is impossible, but there it is, for all to see.
What does it show? That the CCP isn’t really Marxist, and that economic determinism is wrong.