A lot of people are mentioning the affordability of children, yet countries that still have growing populations often have a lot less than we do. They don't have concerns about paying for childcare, that isn't what they do with their children.
They aren't worrying about workers paying for state care because they don't have that anyway. In most countries where the population continues to rise, there's no such thing as a state pension for all, or state provided elderly care.
The problem isn't affording to have children, the problem is what we expect our children to have. Expectations that countries with healthy birth rates frankly don't all have.
The trouble is, most of the solutions to the western birth decline rely heavily on finding ways to meet the requirements of the modern parents.
And the fact is, we can't. It costs a lot more to have children here because nobody wants to bring 6 kids up in two rooms, etc.
In a lot of the developing countries where birthrates are still high, even the basics like education are still a luxury.
Obviously it's not wrong to want our children to have a decent living standard, as well as ourselves. Anyone can 'afford' to have children. Millions of people around the world living in abject poverty are still having children.
We aren't willing to do that, here. And before I get jumped on, I am not saying we should be, but the reality is it is impossible to facilitate an increased birthrate in a society that is used to a much higher standard of living without massive increases in taxation, which we have seen on enough threads, people aren't willing to do.