A Keynes did was to retroactively justify the measure's Capital undertook to extricate itself from the crisis of the early 20th century, providing the capitalist reasoning for the capitalist end of the business-labor peace that produced the postwar consensus. In theory, Keynesianism says that all economic crises are the product of economic under consumption and underinvestment- an excuse for stimulating both, and thereby perpetuating capitalist social relations. Marx transcended the arguments of Keynes before Keynes was born, dealing with proto-Keynesian positions at length in the Gothakritik.
Marxism is objective and verifiable. Marxism holds that end stage capitlaism will produce a "propertyless" working class living on credits and owning nothing - and behold we are entering that age now (and actually have been inching towards it since the inception of neoliberalism in the mid-70s). You do not own your home; you rent. You will not own a car; you will rideshare. You will not own your cell phone; you have a plan. Your health insurance is provided by your employer, even if coerced by the government.
Marxism is objective and verifiable. Marxism holds that end stage capitlaism will produce a "propertyless" working class living on credits and owning nothing - and behold we are entering that age now (and actually have been inching towards it since the inception of neoliberalism in the mid-70s). You do not own your home; you rent. You will not own a car; you will rideshare. You will not own your cell phone; you have a plan. Your health insurance is provided by your employer, even if coerced by the government.