In my personal experience, my Red Sex Links, Red Comets, ISA Browns, Golden Comets, etc. (depending upon formula for the sex linkage between silver hen and red roo).....
I have not had good luck with them living long lives. They have been genetically selected to be laying machines the first 2 years of their life. That makes them genetically very prone to ovarian cancer and other internal issues and not longevity as the commercial industry culls at 2 years. Mine have all died or had to be put down due to wasting by 3 years or so.
However, each bird is an individual. And each environment is unique.
I personally believe in not lighting the coop in winter to allow the hen a natural molt and recuperation time, important for a high commercial layer.
Feed them good quality layer feed with adequate calcium as they have a large calcium need. Keep them parasite free. Clean feed. Clean water. Stress free roomy coop. Free range protected from predators. Good dirt to dig bugs. Happy flock mates.
I've heard a number of them live to be 5 or 6 years of age, and some older. But in my experience, that is not the norm.
Now my backyard mutts....I am amazed to notice a number of them are now 4, 5 and even 6 years of age and still laying at least part of the week....and still a viable flock member.