While the blazers would have almost certainly won the game if not for the block being called goaltending (it's not completely certain... one missed free throw and a 3 pointer sends it to overtime too), there are a few other things that happened at the end of that game. After Aldridge hit a pair of free throws to go up by six with 2:17 to go, the Blazers missed 5 of their 6 shots. In the 18 seconds before the bad call, the Blazers failed to secure three defensive rebounds. That's 8 opportunities to win the game that would have made "the call" irrelevant (or even nonexistent).
This seems more to me like Memphis losing the 2008 NCAA tournament. A team that was in position to win ends up losing in painful fashion in overtime because of a flaw that everyone already knew they had. In Memphis' case, they couldn't shoot free throws. In Portland's case, they don't have a reliable closer.