@Aesthia
No problem, and like I said average age for feral/abandoned cats would definitely be vastly lower. It wouldn't even surprise me if the mean/median oldest age is around 16, or lower, lots of cats die younger than that sadly. It must also vary by region and environment, I don't know if there have been any studies. It'd be interesting to know if cats live longer on average in Japan for example but I don't have any idea.
Still, they can at least potentially live for decades in rare cases, and one-in-a-million odds are the kinds of things legends are born from! Having them live longer is a bit bittersweet, more time together but it hurts even harder when they're gone.