I think that cratering the carrying capacity of the Earth with a climate apocalypse is bad, but 99.9% of the time when people talk about overpopulation, they are promoting genocidal and scientifically backwards bullshit, often throwing China under the bus despite it being far better per capita than the anglosphere and constantly improving.

Degrowth is a much more serious frame for these discussions, not to mention the annihilation of industrial beef farming, which is just an unspeakable waste of resources beyond being cruel to the animals.