It can be a lot easier if resources are more pooled. Society has decided as a whole to adopt isolating philosophies and lifestyles but small groups can reject this and form communes. I know many people raising children in groups like this, and their quality of life is so much higher than friends who chose the "traditional" American lifestyle of a nuclear family I struggle to understand how the nuclear family idea wasn't laughed out of the room the first time someone tried it (it's definitely a new idea, even in my white bread swedish Midwest heritage. I hear stories from my grandparents about how larger families used to live together to raise kids, working with neighbors and etc).

The hard part is of course finding people with roughly the same child raising values as you and your partner, but then again, is that that much harder than finding a life romantic partner with roughly the same child raising values as you? I think most people don't even do that, in my experience a lot of people and couples are totally winging it and marriages occur out of convenience or necessity.