There's a net new 80 million people added to the world every year.
It's already crowded af in large cities with ridiculous traffic, housing prices, crime, and air pollution (think LA, NYC, Hong Kong).
How much worse will it get before we start seeing a lack of food, energy, and resources (ie. metals) to sustain the population?
Not without economic catastrophe. If we lost even 10% of people, global trade would likely grind to a halt, and there would be an energy and food crisis.