This is why life expectancy has gone up, while longevity has mostly remained unchanged (for at least thousands of years). Longevity represents the best we can do, and life expectancy can’t exceed longevity. Life expectancy will asymptotically approach longevity as medicine improves.
I think it's worth noting that we (in the west) have a lot less of most diseases and infections now, stuff like polio, plague, malaria.
I don't suffer from delusions that we have accurate data on conditions like obesity and T2D going back to the middle ages, but we have seen incidence rates of these kinds of disease explode upwards over the last century.
I'd be interested in more detailed data broken down by disease over time.