>humans basically evolved to handle childcare as a society

On that, you are right. It's incredibly frustrating for many trying to raise a family in Western-style living arrangements being so separate from their extended families and community. Child-raising is most efficient when done by a group: alone, it's exhausting and challenging and it's bad for the economy in the long term:

http://www.historyfuturenow.com/wp/why-the-nuclear-family-ne...

Even if you don't care about the emotional aspect, there are many impacts on society caused by the very recent rise of the Nuclear Family.