Yes, but again, there's a difference between a 'vet' and a 'grandpa.' A vet is a guy that may be passed his prime, but can still 'bring it' and can either play close to his peak level, or can still have a major impact.
A "grandpa" is a guy that has been relegated to the 4th line or 3rd pairing defense. They still have all the 'veteran leadership', etc., but because most of these guys are in the 37-40 age demographic, they might be
too old to the point where there is too much of an age gap for effective mentorship.
It's not complete black and white, but there is a difference between a 'vet' and a 'grandpa' (on a semi-related note, it's one reason why I do NOT want the twins to be re-signed when their contracts expire even if it's for substantially less money).
Grandpa's can be good to have for championship calibre teams gearing up for a long playoff run (and so they trade for said grandpa's at the trade deadline).
You need good young players obviously. However - just as a team can't be full of vets, a team can't be full of hair-less 19 year old kids either. The Canucks are not very good because all/most of their young players haven't reached their peak yet, while their vets are passed their primes.
I don't understand why this is so hard to comprehend?
If you are deliberately trolling me however, then I tip my hat.