A Miller trade feels like it's all but inevitable now, likely immediately after the 4 Nations Cup.
And honestly, there's a pretty compelling case for it even aside from what's happened this season.
He's in his 30's, and his play will likely degrade from here. We especially see if for players who play the style he does. Their bodies cannot keep up.
The Canucks #1 priority needs to be keeping Quinn Hughes. To do that, they need to position themselves as a team with a long term competitive window, which means that they cannot have players aging out. They also need to make Quinn's job as captain easier.
The Canucks can get real, tangible assets for Miller that will help the team. They will open up a massive hole in their center depth, but can fill another hole. It's true that you cannot win a trade for a top 20 player who is in their 20's. But you can definitely win trades for players who are in their 30's. From an asset management view of things, the fact that they can get value from Miller should be seen as a win for management.
I also think Miller has been overrated a bit. He's a good but not great player. His best season came from being deployed with Quinn Hughes. It's now well established that anyone who plays with Quinn Hughes gets a massive boost. If they get a center in the trade and deploy him the same way that Miller has been deployed, it's very likely that player will suddenly look like a star.
Don't get me wrong: this trade will weaken the Canucks this season. But they are still well positioned to make the playoffs, and should be able to use the cap space to their advantage to fill holes on the team. In the medium to long term, a trade will make the team better.