You can classify anything as a 'waste of talent' when looking through this lens. Are you a software engineer? If so, then doing literally anything apart from developing software is a 'waste of talent'. Cleaning dishes? Gardening? Exercising?
Maybe if overtime was flexible, you could suggest hiring unskilled workers to do those tasks at home.
I love my kid, but it's not like he's learning cutting edge stuff that requires an engineer to teach them. And there's many hours in the evenings and weekends we spend together where he learns how his dad behaves.
A lot of that develop happens when they are not learning, or at least you don’t think they are.
The bond is there.
If you really want to turn this around, imagine how dependent a child would be on a parent if they never used a babysitter.
He is hardly dependent on us. More on his grandparents because they spoil him, but the first 4/5 years of his life, he would see them only a few times a year.
You don't need to justify working full time, or your wife/husband doing the same, but there is no way childcare in a nursery/pre school is as good as stay at home parents (assuming normal parents of course).
Heck, it is common for kids that are put in nurseries when very young, to develop very very strong bonds with the caretakers, sometimes more than with the parents. (source: studied/worked as one)
My original comment was more targeted to the OPs statement that little kids can’t learn much, so having a parent around doesn’t matter.
As a parent myself, I come to realize that even though you might not think your teaching your kids, you are, even just the basics of socialization and play. And on top of that, those shared activities are was build a bond between you and your child, which is necessary to raise a well adjusted child.
I was replying to gp about using never using nanny's services or how it is a waste of talent for parents to do so if they can have more 'important' things to work.