I think you’re intentionally missing the point. Yeah, condoms are fine. The government mandating when you can and cannot use condoms in order to enforce an arbitrary population number is not as fine.
No, you’re being obtuse. The scenario is a post end of days revival from nothing. Why or how would the government practice sterilization or forced restriction of labor when there isn’t a continuation of current government at all? Its for rebuilding. Creating a new culture. One where you can prioritize education on our balance with nature and the importance to sustain balance.
If your only solution to a problem is the government has to force people to comply, you aren’t really looking for solutions, you’re just trying to shut town the people who are.