There are many discussions of this available to you.. Why you eould deride me for discussing an issue do easy for you to be informed about is quite astonishing. Japan needs women to be married younger,, as it is cultural need for women to be subservient in a marriage. Get them interested in a boy before they have an education or career, seems their solution.

https://www.eastasiaforum.org/2022/11/11/japans-marriage-market-needs-to-break-from-tradition/#:~:text=Due%20to%20the%20declining%20total,to%20maintain%20a%20sustainable%20population.