How is this different to today in countries not living the good life because they have exported slavery to other countries? Africa for example seem worse off than what you wrote. Around 1% at 60:

https://www.populationpyramid.net/africa/2022/

To compare to a time when slaves were near, surely we must add our poor regions, where people work in mines and factories for us, to our life expectancy. Otherwise we are as much comparing Modern Capitalism to feudalism, etc.