At some point this stops being the case. Obviously if the family live on passive income and parents don’t need to work then the opportunity cost is less importa

At some point this stops being the case. Obviously if the family live on passive income and parents don’t need to work then the opportunity cost is less important. If the parents have high incomes then they can, if they are willing, afford to pay for various childcare services. However there is an emotional opportunity cost to this: parents may want to be around and not at work as their children are growing up. Though this matters less once the children are spending much of their time at school.