Incentivising to have more kids is not going to work. Things have changed. A lot of people just don't want to have children, and it isn't a financial issue.
There does not seem to be a strong correlation between countries which make it easier and more affordable to have children, and the replacement rate.
The government isn't just responsible for finance but all of society. Incentivizing kids doesn't have to just mean dangling money in front of parents. Not having government-funded media encourage lifestyles that lead to less children would be a good start.
There does not seem to be a strong correlation between countries which make it easier and more affordable to have children, and the replacement rate.