It all depends on how low you set the poverty threshold. This morning I saw my old Economic History professor Stephen Broadberry get news coverage for a paper that suggests that on average people in several sub-Saharan African countries were not only poorer, but much poorer than the medieval English (less than half GDP per capita, using access to food as one of the main barometers).
True, but it's an indication of how low a poverty threshold of a PPP-adjusted dollar a day is when its below the level of a mostly-peasant population that didn't have access to adequate sanitation, any form of energy other than wood-burned heat, or anything invented after the 1300s
