High birthdates are a problem with scarce resources and tend to be associated with poor treatment of women[1]. Low birthrates are an extreme problem because as people age, they need to be taken care of. Even if that old person is very rich through responsible investments in their younger age, that money won’t bring them the proverbial glass of water without another younger person there.
Like with most things in life, balance is important and hard to achieve.Two to three kids per family seems to be ideal, but comes with an extreme life style hit unless you happen to be very well off. There are many irrational worries too that come with being a parent. While not perfect, I’ll take some support over none. „Too much” support is an ethics/ideology question and also has to do with social cohesion and ability of the society to integrate new members into that cohesion.
[1]https://worldpopulationhistory.org/womens-status-and-fertili...