The only real -life expectancy- data I've seen is all the 20+ year old Hobies and Prindles still out sailing, with their original aluminum masts I might add. Carbon hasn't been around long enough to establish a real life expectancy. It might last longer but it will take another 20 years to find out for sure.

The all carbon mega cat Playstation has been around for at least 10 years I think, sailed hard, I don't know how it is doing structurally today. Many improvements in construction technique have been made since PS was built too.