> If more people meant more technology why didn't China/India bring out the industrial revolution?

England had high population density concentrated in towns, trade with different cultures, high demand for labor after they banned slavery, a tradition of craftsmanship and invention, and a class of people who had a secure income but couldn't grow it easily. All of these factors came together at a time when modern science was becoming established.

India at the time had a rigid social hierarchy where it just wasn't possible to move up no matter how rich you got, and everyone was used to that so there was no real attempt to change things. China's population was high but too evenly distributed and they never had as much cultural diversity as Europe.

> there's some things caused by overpopulation leading to worse quality of life e.g. countries ... where a home with a nice yard is basically unaffordable

Worse quality of life for you. I would take a cramped studio in the most notorious neighborhood over a nice house in a village where nothing ever happens. Boredom would kill me. If it was up to me I would have everyone live in cities and leave the countryside for agriculture with workers coming there on month long shifts as needed. And I think there are more like us.