That is really old thinking

The idea promoted by this book looked quite odd to me, and the recently published opinion of Sarah Harper, former director of the Royal Institution and an expert on population change, working at the University of Oxford, confirms it. In her words, declining fertility rates around the world should be cause for celebration, not alarm. Artificial intelligence, migration, and a healthier old age, meant countries no longer needed booming populations to hold their own. Having fewer children is also undoubtedly positive from an environmental point of view as having one fewer child reduces a parent’s carbon footprint by 58 tonnes of CO2 a year. Capping our consumption is much important than producing more and more goods. The countries in Africa and Asia, where the fastest population rises are occurring, need a bigger share of resources if we are concerned about global inequality rather than overconsumption.

This idea that a country needs lots and lots of people to produce more goods is getting obsolete, and promoting it is simply bad for mankind.