I'm all for having as many children as you can raise, and caring about old people, but interpret the following how you wish. It is a highly anomalous thing in the history that ordinary people receive real medical care when they are unable to do basic tasks themselves. You might have some basic care if your children care about you, but that's about it, and that might be our future and there's very little we can do about it except enabling policies that make having children viable option for those who want to have children.
Only 5% of people work in agriculture and 15% in industry. So we could reduce the workforce by 80% if only people would groom their own dogs themselves and just die when their time comes.
And if not healthcare is another 15%. But you probably can shave off a little from all those numbers if you exclude the time devoted to desperately trying to sell things to each other in the economy of abundance.
Who will do the work required to care for the elderly population?