Five years on the shelf is nothing for a quality cartridge, unless there were egregious problems in the storage or the design/build was defective in the first place. Plenty of high-end MC carts 15+ years or older can still provide quality service today (e.g. Koetsu); I have one myself over 20 years old that sounds fantastic, though it really needs a re-tip due to it high usage in the 1990s.
There are lots of pristine MC carts over 5 years old, ready to provide stunning analog sound.
There are lots of pristine MC carts over 5 years old, ready to provide stunning analog sound.