You misunderstood me, its not just the womens role, we have split the parenting job pretty much down the middle, and we have about as good a situation as a modern family could get - its still very hard on both of us and thats why I can confidently say its a rough job that anyone (women or men) might want to for go.
You said your wife is a stay at home mum and you have split parenting down the middle. That does not sound consistent to me. That sounds more like traditional roles, so why is to so hard?
I was married to a stay at home mum and did half the parenting, but that meant I was overworked and she was not doing very much. It is one reason I am not married to her any more!
My ideal would be something like both working part time and sharing parenting. I blame governments focused on maximising the workforce and GDP. A lot of parents here in the UK drop kids off at school for breakfast and pick them up after "after school" activities. Not much joy in your kids if you hardly see them/