The Canucks were nowhere near playoff contention at that point and Allvin surrendered the Islanders' 1st Round Pick (17th) and the Canucks 2nd Round Pick (43th) to acquire the D man. Hronek came at a time of desperate need for the team for the Canucks, but he fits rights into the team's core and the front office's retooling.
However, at the end of the day, the Canucks can put this one down in the win column. They acquired an established top-end defenseman in exchange for prospects that may never make it to the NHL. Even if they do, we're still at least 3-4 years from them being active contributors to the team. At which point, Hronek will be in his prime.