Totally false. It can be argued that they're not doing enough, but they are definitely trying.
December 14, 2022: "The Japanese government is planning to provide an additional 80,000 yen (€556, $592) to couples who have a child as Tokyo looks for ways to halt the alarming decline in the nation's birth rate."[1]
January 24, 2023: "Japan’s prime minister issued a dire warning about the country’s population crisis on Monday, saying it was “on the brink of not being able to maintain social functions” due to the falling birth rate.
...The government has launched various initiatives to address the population decline over the past few decades, including new policies to enhance child care services and improve housing facilities for families with children. Some rural towns have even begun paying couples who live there to have children."[2]
June 1, 2023: "Japan is investing around 3.5 trillion yen in a push to increase the number of children. The country's acute population problem is getting worse quicker than expected.
Parents will be entitled to a monthly allowance will of some 15,000 yen —about $107 dollars — for each child from newborn to two years old. There will then be 10,000 yen for children from the age of three and older, with the coverage expanded to include children in senior high school.
The government also plans to open up nursery school or day-care center places to children, even if their parents do not have jobs.
It will raise childcare leave benefits, starting in the fiscal year 2025, so disposable family incomes remain unchanged for up to four weeks even when both parents take leave.
The measures also include increasing paid parental leave and providing subsidies for fertility treatments. "[3]
[1]: https://www.dw.com/en/will-japans-new-plan-to-boost-birth-ra...
[2]: https://www.cnn.com/2023/01/23/asia/japan-kishida-birth-rate...
[3]: https://www.dw.com/en/japan-to-channel-billions-of-dollars-i...