It wasn't that he wanted to leave. I totally get that; he felt he had a couple of years left to contribute, and wanted to go for a cup.
If he told management that and said: "Please send me to a contender", it would have been A-OK. Still self-serving, but understandably so.
However, demanding he be traded to a specific team gave the Canucks zero negotiating power. He put his own desires ahead of that of ownership, the team, the coaches, the GM, and the fans. It was a very selfish move, and it pissed people off.
At least from my own perspective, I don't hate the guy. He gave his all to this team while he was in Vancouver. But he cannot expect to be remembered fondly when the very last thing he did is screw the team. Everyone forgives at different speeds. Some never do. That's a fact of life.