Edit: s/didn't live/rarely lived/
>60s or 70s not uncommon.
I would love to see the evidence you're referencing.
> Life expectancy being 25 doesn't mean nobody lives past 25.
You're absolutely right.
The Sami, as I mentioned, have been studied. They are a tribe of reindeer herders in northern Scandinavia. They eat a diet consisting of almost exclusively reindeer meat. They have lower cancer incidence than Finns (https://onlinelibrary.wiley.com/doi/full/10.1002/ijc.10486).
Hong Kong consumes more red meat per person than the U.S. and they have the highest life expectancy in the world: https://beef2live.com/story-world-beef-consumption-per-capit... https://en.wikipedia.org/wiki/List_of_countries_by_life_expe...
Very far from a typical meat diet (quoting from your link):
"The dietary habits of the Sami differ from those of the other Finns. Reindeer meat (low in fat) and fish have been important foodstuffs in the diet of Sami people. Intake of vegetables and fresh fruits has been low, but berries were eaten, especially by the North Sami. Although nowadays dietary habits have become more similar to that of the rest of the population, still more than 90% of male Sami reindeer herders eat reindeer meat at least 3 times a week and almost 50% eat fish at least twice a week. Reindeer meat and fish contain high concentrations of healthy lipids, trace elements (e.g., selenium), minerals and vitamins. Arctic people usually rely on blood, liver or kidneys from animals to obtain adequate nutrition."
http://www.unm.edu/~hkaplan/KaplanHillLancasterHurtado_2000_...
As another poster pointed out, we can't really know how long people lived in prehistory. The numbers come from contemporary hunter-gatherers.