He's never been the fastest player, but he remains highly productive, reliable, and elite on faceoffs. He also keeps himself in top shape, so concerns about his age are less of a factor. On top of that, he understands the Leafs have other contract priorities and is willing to be patient.
The rising salary cap gives the Leafs more flexibility, but how long they wait will matter. If his asking price isn't manageable for Brad Treliving, things could get complicated. The market would likely offer him more than the Leafs are willing to pay, but everything suggests he wants to stay-as long as the deal is reasonable.