Remember, this is popular entertainment, so the movie hero is meant to be aspirational. Even if we don't literally make an action figure out of him, we're still meant to -- a little bit -- take cues about our values from him. So what cues are we taking?
First, that suffering is noble, and second, that the status quo is great. Our heroes are, across the board, people who suffer and die in the name of keeping things exactly how they are: Jack from Titanic sacrifices his life for his wealthy girlfriend. Frodo from Lord of the Rings sacrifices his innocence, sanity and (sorta) life (it's vague) to protect the Shire. You might argue that Dunbar in Dances With Wolves is trying to stop American westward expansion, which is a criticism of the modern world as we know it, but no one dared to give that movie an award until any hope of stopping the genocide of Native Americans had been dead for over a generation. The message of Dances With Wolves is "this bad thing happened, and now it's safe to feel guilty because there's nothing any of us can do." If the movie had been about a violent revolution on a modern-day reservation, the Academy wouldn't have even noticed.
Even The Hurt Locker ends with the hero going back to war, giving up on himself and surrendering to his addiction to war and adrenaline. I admit that I haven't seen every single movie on that list, and there might be a couple outliers that the commenters will point out, but I've seen most of these, and every single one is about people nobly suffering to keep things exactly how they are. That's the story we're supposed to think is honest, important, and serious. I'm not saying that these types of movies are bad in any way (I'm a huge fan of every movie listed so far) but isn't it weird that this is the only moral we like to give awards to?
Think about what that message means for poor kids growing up in a ghetto, or women who get harassed over literally whatever they happen to be doing that day, or the impressionable teenager being sent to fight for a morally ambiguous war, or gay kids getting beaten to death in the street. "Your suffering is noble," the movies say. "Suffering means you're respectable," the insulated, multi-billion-dollar international industry says. "Being in pain means you're important. You're making this country great. Thanks for that. I'm going to enjoy an old fashioned and watch Pacific Rim on Blu-ray," says the single most far-reaching and powerful propaganda tool that has ever existed in human history.