Just because Marty isn't as athletically gifted as he once was, does not mean his opinion should count for less. Brain trust in the Devils locker room is Elias, Marty, and Jagr to a lesser degree. If all 3 of them feel this way it is a pretty damning assessment.
I'm not saying he's wrong, but he's also a big part of the problem and a big reason we're mediocre and thus probably shouldn't be calling anyone else out in this situation. If Jagr said it, well, I'd allow it because he's played his ass off and given his all.