I'm currently reading Sartre and I am seeing distinct similarities between his philosophy and mgtow:

He argued that the use or purpose of a tool - or any other man-made product - dictates it's form. For instance: scissors need to be sharp to cut paper, with ergonomically designed handles for a firm grip. However, humans have no specific purpose and are free to shape themselves. We need to create our own purpose and not follow societal customs/ subconscious patterns of behaviour.

Man, therefore, should see the world in which nothing is preordained. It is his responsibility to pursue happiness for himself and decide what is a worthwhile activity.

Furthermore, freedom is the greatest responsibility of all. Man is solely responsible for his life choices and also their impact on mankind. And, with no external principles or rules to justify man's actions, we have no excuses to hind behind for the choices we make.

For Sartre, then, every man is 'condemmed to be free'.