The New Left/Frankfurt school remagined Marxism in the postwar decades.
The Bougies vs Proles narrative became outdated by the mid-20th Century, so they redefined it from class struggle to any kind of power discrepancy; the "oppressors" vs. the "oppressed".
Communist sympathizers in the West (much to the delight of the Soviets) goaded on the Civil Rights Movement, feminism, and the Sexual Revolution. Fracturing social cohesion in the name of "equality" was their goal.
Hence, the Left now consider any undesirables to be "marginalized" for no good reason, and that anyone who has a problem with said undesirables is just a petty, intolerant bigot. Why else would they simp for objectively horrible people?
Which is a classic Marxist rhetorical tactic, by the way. They cannot take even constructive criticism. In their minds, the only reason anyone would criticize a Marxist or their so-called "oppressed" pets is because they're an apologist for the "oppressor" class.