This seems to be a huge shift from the previous generation. My father and most of his peers worked long hours and contributed little to childrearing.
I'd guess men don't volunteer to be primary child rearers because stay-at-home jobs have been relatively rare, prior to the past 4 years, men tend overwhelmingly to want to support a spouse than to be supported (which is probably why gay couples have greater household incomes and lower divorce rates than all other categories), and women tend to be hypergamous in mate selection. It's not that there's no incentive to stay home (if you like your children, at least, which I hope is true), it's that there's a strong incentive to go to work.
In my particular situation, tax and childcare would eat most of my wife's income, so she'd be spending 40+ hrs/wk working with other people's children in exchange for less time with hers. She'd rather work with our children and be able to take an afternoon nap.
Would we both prefer to be independently wealthy and not have to work, sure! Might one or both of us work anyway? I probably would. She probably wouldn't.
The remainder of your message appears to be uninformed condescension. My wife is not a chattel slave. Her primary focus is child rearing and home making, but it's not her sole occupation nor solely her responsibility.
There are parts of being single we miss, and parts of being childless we miss. That doesn't change the fact that we've worked very hard for the life we have, find it very rewarding, and wouldn't give it up easily.