Question: Some governments want their citizens to have more babies. That means more people will be reborn in Samsara. Is it not against Buddhism, whose aim is to end rebirth in Samsara?
Answer: Advocating more births is just a political suggestion for the maintenance of population; it is not mandatory law. Good Buddhist parents, challenging as it might be in our times, might be able to nurture good Buddhist children, who gain the precious human rebirth to learn the Dharma to advance spiritually.
If there are no beings with karma to be reborn human, even compulsory law cannot make it happen. The Buddha never taught that it is a misgiving to have children, unless one is a monastic who is supposed to be celibate. However, he never said everyone should have as many children as possible too. It is a personal choice ideally based on mindfulness of couples’ capabilities to be good parents.