I had a 120 minute IPA that was over four years old. Cloyingly sweet, but then it's pretty damn cloyingly sweet when it's fresh too. I've had about ten bottles of it ranging from 4+ years old to as fresh as it gets. I can't say I have a preference in that one, TBH.
I had a one year old bigfoot ale that was still damn delicious. It's very hoppy fresh, and was still pretty hoppy after a year. But that's barleywine.
Now aged pliny would be a sacrilege...
Two-hearted and hopslam would be wrong to age, although again, aging pliny would be a crime against humanity.
As a general rule, I agree that IPAs should be fresh.