Cultural Marxism was a response to the flaws of orthodox marxism.
Marx himself thought of society as being a war between economic classes, and that the working class was the engine that would lead a revolution and overthrow the capitalists.
The problem is, Marx didn’t live long enough to actually organize such a working class revolution. And when his successors tried, they discovered a small problem: namely that the working class doesn’t want revolution, and in fact the working class is the most conservative class in society, even more so than the capitalists (who led the revolution out of feudalism). Economic conflict couldn’t overcome forces like religion and patriotism and tradition.
What to do? The British Fabians, a group of Marxist intellectuals, realized there was one class that was open to the idea of revolution, namely intellectuals like themselves. They looked down on religion and tradition as superstition, and instead of loyalty to their nation they felt loyalty only to “The People”. (Only in the abstract, of course, they didn’t seem to want the company of actual dirty uneducated people.)
Lenin put this into practice. His Bolshevik party was lead by intellectuals like himself and Trotsky. It was not for the working class would not lead the way, instead the Bolsheviks would lead the working class.
Attention must be devoted principally to raising the workers to the level of revolutionaries; it is not at all our task to descend to the level of the “working masses.”
Lenin, What Is To Be Done?
In Italy, Gramsci took Lenin’s idea a step further. He answered the question why the working classes was conservative, it was their attachment to their culture. Intellectuals were one group that could overcome that attachment. But what about groups that weren’t really part of the dominant culture: racial and religious minorities, criminals, feminists unhappy with the role of women, rebellious youth, immigrants, homosexuals, everyone who lived on the fringes. If somehow all them could be united in hatred against the dominant culture, you would have a force that could reshape society. Cultural marxism was born.
The Frankfurt School brought these ideas to America. Every aspect of traditional conservative culture was given uncompromising adversarial critique (critical theory). It was racist sexist anti-semitic homophobic xenophobic sexually repressed etc.
And here we are today. It worked! A coalition of the fringes, united against the historic core: white Christian men. Democrats vs Republicans. Long after the Soviet Union has collapsed, American politics and every college campus in the country is shaped entirely by the ideas of cultural marxism.
The term “cultural marxism” makes sense when seen in this history. The problem is, very few people know this history, and when they see the term they have no idea what it means. It looks like jargon.
One more colorful term is “coalition of the fringes”, coined by Steve Sailer.
And for a pair of even more clear, direct terms, try anti-white bigotry and anti-male bigotry. Because nowadays, that’s what it amounts to.