Is there any way you can upload some photos showing the issue? Perhaps a better description of what is deteriorating? Other problem spots? Deterioration around dropouts?
Perhaps some aluminum corroding somewhere?
There is a lot of debate about the longevity of Carbon Fiber frames.
There are many carbon fiber frames > 20 years old still on the road, but perhaps not getting hammered with a lot of hard miles every year.
Most pro racers retire their bikes after a couple of years. Sometimes they get sold for a "second life". Still, tens of thousands of miles of high power riding every year can be hard on a bike.
On the other hand, a casual weekend rides, and the bike could last quite some time.
How many miles do you do? What type of riding? Racing? Crashing?