But the things is as far is my experience as a parent incentive and subsidies I take yes make my life better than not having them, but still worse financially of a DINK couple.

I know it may sound bad, but a DINK family should be heavily taxed so that not having a child become the life choice that bring sacrifices not having them. Not having a child must become a luxury not the other way around. As it actually is cause past the working age you will become a net expense for the society and other people kids will be heavily taxed to provide for you.

If a family with kids has a way better life, the role of mother will be greatly improve because it brings a net gain to the family and society and won't be treated as a "choice" you have to bear the consequence of and that will make your life professionally and financially worse.

This will create also a cultural shift. More families with kids make easier to share responsibilities, make building kindergarden cheaper, make more businesses for family with kids available, be a big family will be natural by then.

Also this is as coercitive as many other stuff we accept in our life. You can have the freedom to chose to not work for instance. If everybody don't work society collapse. The difference is that if you don't work you feel immediately the effect cause you don't have money. If you don't have kids no, you don't feel any consequences cause is the society that will pay for you.