Marx never set foot in a business. How would be know if people were being oppressed or not?
He oppressed everyone who knew him, he freeloaded and borrowed money from everyone who would let him.
Bernie Sanders also freeloaded just like Marx, until Sanders became a senator and got rich.
For well over a century, little Marxist are out there preaching Marxism as he was an authority on what he talked about. Marx knew squat about what he was talking about.