Life is a recursive function with an unknown conditional inside for when to stop.
There was a famous theory in the '60s called the
behavioural sink. In a series of experiments, rats were placed in an enclosed space with unlimited access to food/water until they inevitably overpopulated; it was observed that pathological behaviours from cannibalism to social withdrawal emerged as overcrowding worsened.
It was hypothesised that human behaviour would similarly descend towards self-destruction in the face of excessive population. In practice, this process has been complicated by the various systems that we have to manage antisociality; easy access to food, distractions, policing and social pressures to inhibit those dark tendencies. The results are predictable when these systems break down, of course. The silent massacre of the ecosystem is a key giveaway for humanity's primitive inner state lurking beneath the surface.
The younger generation are less brainwashed by the social expectation to procreate endlessly. I rarely see huge families like my maternal grandparents' 6 children. More importantly, there is also the expectation of higher standards of care for children. This is a step forward.
The greatest tragedy is that often, the ongoing population expansion is driven by corrupt social pressures. These include a positive-biased attitude towards life, a lack of individual responsibility regarding ecological issues, a romanticised image of parenthood, censorship of parents who admit that they made a mistake, and the influence of government/corporate bodies who have a financial incentive to grow the numbers of humans. As commonsense prevails, the world should naturally move in a better direction.