I remember posting last year about something Patrick Mahomes said early last NFL season. His team was winning, but they weren't playing very well and this is what Mahomes said.
“If I start playing better, everybody will start playing better,” Mahomes said, via Adam Teicher of ESPN.com. “I missed some opportunities throughout the game and so I’ve just got to put us in better positions and [start] making better decisions so that the guys can go out there and work for me and make plays down the field.”
I said I wish we had a leader like that. In those few bolded words, he acknowledges that he hasn't played as well as he can, he implies that the same goes for the rest of the team as well. He also assumes the leadership role by saying if he leads the way, he knows that everyone else will follow. And guess what, they started rolling, and rolled all the way to another Super Bowl. Now that's what leadership looks like.
Matthews is the captain, so the lack of leadership isn't all on Marner, I'd say that as captain it's mostly on Matthews but still, as an assistant captain it's partly on Marner and it would be a big positive for the team if he came out and said something like Mahomes said. Instead, after another embarrassing loss Marner says "I liked it. I thought we played well, I really did".
Sure, it's one quote but as many have said, it's a symbolic part of a big picture that we've been watching for years now and it's not a pretty picture. He's said similar things before, that quote seems to be an accurate reflection of his attitude and if that's his attitude, it doesn't give much reason to hope that anything will change.