Not a lot of people in the world saying "Look at my huge salary, I can start a family!! Society is doing so well that I think it's a great idea to bring children into this world that totally wont turn into Waterworld within my lifetime."

Because nobody can afford to support a family, that's why. I live in NZ, I can barely afford to make ends meet myself, let alone support multiple people.

And it will stay that way unless a family with 2-3 kids can afford to live comfortably on a single income.

We're in for a real treat when most of the population is elderly and there's nobody to fund them or care for them.