Having children is a choice, it's the parents responsibility not the governments.
The last thing the world needs right now is more people, it'd be different if there was a burning need for a larger population
You’re conflating environmental issues with the economic systems our country operates on. They’re separate things.
Economically we absolutely do need more children. Their taxes will pay your pension. They’ll be the ones wiping your arse on your care home, treating you in hospital. The system needs a constant supply of new humans.
Plus, I think you have to take into consideration the strong biological need for humans to reproduce. To define it as a ‘choice’ is far too simplistic.
Finally, economically we’ve created a world where a) working 9-5 (and far beyond) is an expectation of employees and b) two incomes are often required to buy a house and fund retirement.
It’s pretty shitty, frankly, to support this system, yet tell parents airily that ‘their children are their responsibility’ with no provision for those children when school hours are up. It’s literally asking the impossible.
The Scandinavian countries show us how this can be done and they reap the rewards with more equality between men and women.