>>279913234 (OP)Age gaps in any media are problematic. You have to demonize them. If not, people may start thinking it's not that bad for a young woman, or a girl, to be a partner with a (financially) mature man.
By taking in a daughterwife a man may:
- Offload the financial burden from her parents, allowing them to have more children. Especially relevant when it comes to single mothers;
- Ensure that the girl starts having children as early as possible, increasing her baby-making efficiency;
- Interfere with her school education, thus leading her off the path of pursuing a career.
Quite bad, eh? So, you should teach every girl that adult men are all scary bears looking to do evil to her, preferably from an early age. Also, teach men that they're evil if they think of dating somebody a few years younger than them.
This way, a woman will settle down with a man in his 30s by the time she herself is 30, allowing her to produce only the number of kids the modern family can support at a time. Should the degrowth accelerate too quickly, simply import foreigners from where the policies have not yet taken as much the effect.