All of your assertions are false. Male wolves and foxes help with child rearing.
Aka Pygmy Men breastfeed (some men can lactate a little) Most Women outside these tribes don't look for it in a man. Whereas there's do.
Social Services does take children away from there parents and raise them instead.
It's only culture that says just the bad children.
Colonialism commonly took natives away to be raised by society instead.
The kibbutz movement used collective child rearing. They thought it was the only way for equality.
Nuclear families are mostly a western thing. Plus we see more and more young people living together in shared housing.some in a family atmosphere. Why not shared child rearing?
Of course if there are good reasons then someone can provide them righ