If economics were zero sum, wealthy countries would cause a decrease in the standard of living in other countries. Over the last hundred years worldwide basic e

If economics were zero sum, wealthy countries would cause a decrease in the standard of living in other countries. Over the last hundred years worldwide basic education and literacy are closing in on practical limits while child mortality has decreased to what’s close to its practical limit. Is that because all countries became economically wealthy or because enough value was added into the world economy that excesses could be used to provide education and sanitation to people regardless of their status in the world?