Do you really think the elites will keep us plebs around if they do not need us? The only reason we plebs exist is because they need our labor/ingenuity, and perhaps use us a crucible from which new elites are born. Once they do not need us due to longevity, automation and AI, our reproductive capabilities will be severely limited in the name of reproductive freedom, and us plebs will be slowly made extinct except for an obedient few. The elites will go on to become a superior species either through artifice or natural evolution. That is how universe works.