The Legion was made to be a warrior society as Ceasar saw that was foolish trying to build a new society copying a framework that doesnt exist anymore like NCR is doing and he would reboot things from a previous state as the material that made the big pre war Nation Estates collapsed, the NCR was creating a new Nation using symbols that are dead and cant hold the loyalty of anyone, so its fate was corruption, division, strife and collapse.In the end, most people see the old world with nostalgia, that is why the NCR was created but in reality, you need more than some vague ideals to make people truly unite on a common cause. On the Wasteland, survival is paramount, so a society that focus on that with no nonsense is the only thing that can survive on the long run, being strong to survive is something anyone on the Wasteland can relate to from the tribals to the NCR citizen.
Misogeny... the Legion doesnt hate their women, if they did, they would end like the people on Nipton did, women are just seen as not fit to rule because to rule on the legion, you must be willing to kill and die also accept that if you fail at both, if you refuse your destiny as a man, you will end as Joshua Graham. Being a ruler on the Legion is a position of importance but that is something that comes with a heavy price, the Legion doesnt care about your humanity, your emotions, to rule must be a burden not an easy ticket to priviledge (as most modern fags think, that is why they want women legionaires so much, not realizing that if you rule on the Legion, you are expected to die), you must do your duty until the end, men are expected to die and when the time comes, you must, that is the man fate, doesnt matter his position, this isnt expected from women and because women arent expected to die, they are also not fit to rule and seen as weak.
However, this women being weak is different from the treatment they give to men that are weak, the Legion expects the women to be weak (at least in the Legion ruling currency of killing and dying). Women are weak by their Nature, they shouldnt be hated for that because they have no choice, so they see women fate to having babies, if men fate is to die, why women should have priviledge? Also, from the point of view of women on the Legion, they dont see dying brutally on the battlefield as a great priviledge they are dying for to have, Fallout isnt supposedly to be fantasy where being a warrior is something cool. Survival is the only thing that matters. However, a man being weak, that is a choice and you must be punished by your choice... on a warrior society, if you were too much of a coward to not even die defending your village, you deserve to be a slave, you are a plofigate and that is exactly how Vulpes Inculta treats Nipton.
It is debatable if a society like that can keep that culture for long after there are no more enemy to fight and complacency starts seeping in but at least you can argue that Ceasar was right, you need to build something that actually fits the world you are in, later, the Legion might even change but it would be worse trying from the begining building something on foundations made of sand. Of course, if you are a tard that can only see the world through 2021 eyes and confuse your ignorance with morality, you will just see the Legion as misogenic and cruel for having slaves and do exactly the mistake those modders did, the question of ending slavery and having women legionaires would undo the Legion as that is against the core of beliefs that actually hold it together.