> Perhaps the price of living to which you are accustomed to is absurd.

That is not really an actionable observation. The Netherlands is an extremely dense country already, what is OP exactly supposed to do to make their cost of living non-absurd?

> Couples having been raising children with much less for mill

It wasn't just couples then, though. It was the entire village or neighbourhood: cousins, aunts, neighbours, godparents. Nowadays our society is so fragmented that you indeed usually are alone to tackle everything. This change from extended family to nuclear family model definitely has some impact on total fertility.

> Children have a lot of economies of scale. If one spouse stays home to watch them, that covers as many kids as you have.

Which also means that there is no spouse's income anymore. Unless your spouse makes really little money, you will end up in a similar financial hole either way.

> Spending time with grandparents is also common. This is both cost effective and facilitates generational knowledge and culture transfer.

If people have kids in their 30s, the grandparents are quite often too old and sick to help. They may also live way too far to be able to visit daily or even weekly.