Men going their own way. I think the original intent was for men to take all the time, energy, and money they would typically spend on pursuing and maintaining relationships with women and put it all toward self improvement and activities that they enjoy or feel are important to them instead. Because they disagree with the institution of marriage and also to avoid to lopsided consequences of divorce, and to avoid the costs and commitment associated with chidren. But like everything else in the age of the internet I'm sure the movement has skewed toward the extremes and morphed into some strange former shell of itself that is now popular to make fun of. In fact I am sure that's what happened, because OP mentioned MGTOW folks with incels, which are just unhealthy or ugly men who hate the world because they can't get pussy. I'm sure at some point there was a group of relatively normal people who were into that sort of thing and their lives benefited from it but like I said the internet probably ruined it and all the normal people stopped chatting about it because of the negative connotations.