When did the establishment start referring to developed nations as the “rich world”? That reeks of the kind of globalist elitism that conspiracy theorists go on

When did the establishment start referring to developed nations as the “rich world”? That reeks of the kind of globalist elitism that conspiracy theorists go on about. Many an undeveloped nation is undeveloped because of the people who live there and their culture. They should not be considered some sort of baseline.