Seems that there is lots of handwringing over the population decline throughout most of the world.
I mean, I just can't imagine what the government incentive would be to convince the public that brats are worth it and the most important job in the world and that the government will provide a safety net
finances, etc. will all just work out even if a person can't afford them.

China is more blunt than most and refers to them as a "consumer good" because that is exactly what they are. Each of those "lil fwetuur taxpayers" consumes numerous additional consumer goods which is making others wealthy. And they have it all mapped out as to what people will buy for brats from the cradle until they become adults. They don't want anyone to opt out of breeding. They know that most people without brats are able to spend/consume considerably less to live and avoid the overspending from stressing with brats. The company charts and spending projections don't work unless the childless are anomalies.
Hardly anyone raises a brat to adulthood and tells everyone they know that it was a bad investment because that means social suicide. I'd bet a healthy percentage of people wouldn't do it again for anything.
It is like so many religions which offer an incentive after death if you do everything they say and don't question them, it is all about the long-term benefit after all!
Look at the USA and women's reproductive rights (or lack thereof) in 2023.