I want to look at his playoff performance, not just this year but in all 3 playoffs he's been in.
On a simple PPG metric (because that levels it out for players who weren't able to play in all games), he's been very good for us.
2018: 0.57 - T4th on the team, behind Marner, Reilly, Marleau.
2017: 0.67 - T3rd on the team, behind Reilly and Matthews.
2013: 0.40 - 10th, behind JVR, Franson, Kessel, Gardiner, MacArthur, Kadri, Lupul, Hamilton, Phaneuf.
Of course he was injured in 2013 which may have affected things. Of the guys in front of him back then, only JVR, Gardiner and Kadri remain with the team, and none of them produced above him in the following playoffs.
This was an off year for him in the regular season. Does it mean he's done? Maybe. Maybe not.
I don't think you can just write off his FO and SO strengths either. He's replaceable - everyone is, but easily? Not convinced. I'd be happy to see him back on a reasonable contract. At his age, he's probably reached his peak in terms of play, dollars and term. 3-4 years at 3-4 million works for me.