If China had tried to pay the same amount of welfare for more than 1 child, it would have been too costly. Plus the economical aspect "so called one child policy" of family planning changed very little, it was the accompanying sexual/workplace liberation of women that followed decades after. For 20 years after the economic one child policy begun, people simply tanked paying tuition etc for more children because most people who have 1 child want the child to have a sibling and the cost is negligable. Fertility fell in the early 2000s only.not necessarily true, i wager that had it not been the one-child policy, China would be facing a bigger population cliff now, because overcrowding would be worse.
You can't have your cake and eat it too. If you have your wholesome 5 kids and a farm, you're not gonna be the world's best at science at the same time. Top tier academicians need academic wives (or they are themselves the wives). These wives don't have 3+ children, or even have children at all. But they're needed as social support to the people pushing ahead science and industry, so we can have the biggest economy in the world, the most scientific output and citations etc.
If Chinese were told to just be chill, just live on welfare with 3 children in big houses, we'd end up today with a social life and TFR like maybe Sweden or Denmark. And are these nations known for tech prowess or innovativeness?
Btw notice how even in the best of situations, TFR isn't at replacement levels and these chill eurocucks are busy flooding themselves with MENA because they don't have the tech to solve their demographic problem. While China has a 0.5 worse TFR bigger problem, it also has infinitely better ability to solve demographic challenges with real solutions. Developed countries period struggle with compensating a population boom that exceeds the natural ability to sustain. Euros have made themselves the worst of two worlds where they're too lazed out to find real solutions but also not birthing children anywhere near the lemming like rates needed to meatwave through a population "cliff".