Remember, you're judging this based on people who are dieing in their 80s today, think about what life was like 60 years ago when they were in their 20s, open coal fires, smoking and passive smoking, little to no understanding of health and fitness (general population), little to no health and safety at work regulations, little to no enforcement of FDA regulations, little to no understanding of the effects of alcohol, obesity etc. Not to mention the effect of caloric restriction, intermittent fasting, Metformin, yamanaka factors, resveratrol, these will have a compounding effect to the point I believe anyone born 1980s+ will probably have an average life span closer to 100 than 80. That's assuming no further medical advancements between now and then.