I don't disagree with you that we need more out of Matthews but quite frankly he does show up in games 5 to 7
IMHO if he wasn't saddled with the dead weight that is Marner I think Matthews would have done more. He does play heavy, wins board battles, lays body; but when he makes the play Marner is just figure skating and turnsover the puck all the time in the o-zone.
If Matthews is always supposed to be a shooter it is easier to defend him; but when Matthews makes the play nobody on his line would take the shot and Marner would ruin any offensive momentum in the o-zone.
I'd like to see Matthews without Marner for extended period of time. He was pretty good in Gm 2 this season; then he got sick which sucks. And he is the one that set up the goal in Gm7 for Willy; and wasn't on ice for goal against even though he wasn't 100%.
I do agree that given Matthews' AAV, his output must be more and he must make his linemates better. But for that we must see Matthews without Marner. I think Domi-Matthews-Bert line was pretty good!