The left is composed of two factions, not one. The left is the high within society aligned with the low in society to destroy the middle in society. [1]
When the power of the upper class is not secure, or somehow threatened by a middle class, the upper class forms an alliance with the lower classes. Today, you see the highly capitalized media powers (like Big Tech and primary media corporations) and other "woke" corporations forming an "alliance of the fringes" with historically marginalized groups, against the more traditionalist middle class. In the past, Kings would form an alliance with peasants to fend off nobles.
Bertrand de Jouvenel described this dynamic early in the 20th century, but it's a common refrain throughout history.
Neoabsolutism is a modern framework for understanding this dynamic.
[1] https://neoabsolutism.wordpress.com/2017/07/03/high-low-vers...