Odd how some things don't last as long as they used to, but others last way longer. For example, when I was a kid, getting 125k miles on a car was good. By then serious rust and the rings were toast. Now days, over 200k miles is expected.
As far as a GFCI, I would think it's more of a number of trips that determines end of life. Or heavy loads. I had GFCI's in a seldom used bath for 20 years. I tried using one in a home made extension cord splitter for a safer work site. Burned up in a week!
I also have been chairmen for a NEMA standards committee, all manufactures. NEMA = National Electrcal Manufactures ***. All members are representing manufactures. We write the standards because we know the products better than most anyone. We lso know the weaknesses and limitations of a product. This is often the basis for Type, Sample and Routine testing. Recently the NEC contacted NEMA to "push" application limits. We refused because we know the limits.
So when I see packages stating "life expectancy", I take it with a grain of salt. Like change your smoke detector batteries twice a year even though they have a 5 year shelf life!
A bigger concern of mine is old receptacles a switches. You know the receptacles where the male plug just goes in with hardly a push, or worse, falls out! Switches buzzing. Only device to protect are arc-fault breakers