>increasing an economy’s population tends to increase its aggregate output at an even greater rate than the headcount, ie average wages increase. That's true o

>increasing an economy’s population tends to increase its aggregate output at an even greater rate than the headcount, ie average wages increase. That's true only if you cherry-pick certain countries with already booming economies, like the US, where adding more workers adds more fuel to the fire, especially in the low interest environment of the past 10 years. But most other countries with much slower economies, won't benefit from even more workers the way you described ( average wages increase) but more like average wage decreases. Adding more workers won't benefit a stagnating economy.