That you phrase it as a "vacation" and can't seem to put a dollar value on it but obviously less than a couple hundred dollars a week really points to the idea you have no idea what you're talking about.

I don't think anyone thinks 12 weeks with a newborn is a vacation, and yet most people probably wouldn't trade that 12 weeks with their newborn for anything in the world.

> I'm not ignoring this cost

You literally are ignoring the cost, as its not your given model. And its not a cost that will only be borne by the immediate caregivers, there are knock-on costs throughout society that will be felt by this change.