Yeah it's bizarre to think about, but a lot of royalty lived until their 70s and 80s, even in ancient times.
Turns out just having steady access to food, living a low stress lifestyle, and not having to wade through literal shit on the streets was all it took for some lucky ancient humans to have the same lifespans as modern humans.
Also, food in general wasn't poisonous. And if those royals actually lived even a modestly healthy life (not drinking too much, not using lead based makeup, or their doctors poisoning them with mercury etc), then they could easily live a lot longer.
Turns out just having steady access to food, living a low stress lifestyle, and not having to wade through literal shit on the streets was all it took for some lucky ancient humans to have the same lifespans as modern humans.