Why do constitutions not incorporate a clause on population control?
A vast majority of modern states don't have a explicit constitutional clause on population control either (that I am aware of). It seems fair to surmise that it is the consensus of the majority of governments that letting their populations grow without control is a good idea.
Question: What would be some of the key considerations/challenges in outlining a constitutional policy on population control?
I am asking this question in the context of emerging problems such as climate change, automation and now the pandemic as these factors have (and will continue to) put immense stress on available resources.