Industrial societies haven't been very good at realizing technology and market forces have broken and will continue to break the Malthusian cycle. Nor do many people realize how fast birthrates are declining (even outside the Industrial world young countries are aging quickly as they industrialize).
A lot of well-meaning people think our planet holding 7 billion is dangerous without thinking about birthrates or how population growth is seriously slowing, so they demand immediate government action without thought to how people can sort out their problems.
Pretty much why young people love socialism: it's easier to see every problem needing government action rather than let emergent resolutions arise.
I tend to go with one of Isaac Arthur's (youtube.com) irritatingly positive outlooks on humanity that Earth could support a trillion individuals, if only humanity would get its shit together.
Edit: figured I should add the link
(post is archived)