Some people see the movie and expect some thing from a Superman film. I expected that too. I wanted to see the same things everyone wanted to see: a larger-than-life superhero saving the day for the people of Metropolis. I think everyone wanted that.
Superman's longevity as a character has given him a very peculiar weakness that only applies to gods: it seems he cannot be portrayed in any other way than how he has been portrayed since the 50s. As a character, he's in danger of becoming a mere symbol for future generations. You can hear it now from people, especially the younger ones. For me, I can't imagine a world where Superman has become like Mickey Mouse and the other Disney characters. They only appeal to a certain age group and after some time they're just symbols for a big company. He is too good for that.
MOS wanted to remove all that baggage assorted with the Superman character. It wanted to go back to the basics and humanity of Superman. Perhaps for some it was too gritty a pill to swallow: too much realism on a hallowed character always brings out the traditionalist in all of us. But for Superman as a character to continue on, MOS did the right thing and shook the establishment a bit to show that Supes is as dynamic as the others.
There's a reason why some characters fade into oblivion. Some of the superheroes in the 30s have been forgotten, for various reasons but mainly because they need something audiences can relate to and that reflects the current zeitgeist. Batman and Superman writers have always done this, because they understand that for a character to remain in our imagination, we should be able to imagine that character facing the same issues we do and seeing our world. You know which character is doing better in terms of this.
Unfortunately some of us have not been able to imagine Superman that way. We want to protect him and keep him in that glory that he basks in. Even Batman sometimes does this, when in some iterations he'd rather do the bad stuff than Clark because he can't bear to think that a super-good being like Clark would be tainted with some kind of vile deed.
MOS wanted to take Superman off the pedestal that writers and fans have placed him on, and treat him the way a good storyteller treats any good character: take him to situations and problems he has never faced before, give him qualities that people would identify and wish for, and make people THINK about their place in the world.
As a character, Superman has always done this for me, but in the past few years fans and writers seem to think he's Untouchable and have set limits on his portrayal like he was Moses or Jesus Christ.
You can argue that MOS Superman didn't even have the basic qualities for Supes, but here we can agree to disagree. MOS showed a boy who wanted to do good, despite what he heard from his foster parents. It showed a man who was willing to help people even if he was mistreated or bullied. It showed a Superman who despite his doubts, chose to save a world that so far had shown him little kindness (apart from his parents and a few friends) and do what for him was a terrible decision.
And yes, I had to see it a second time to remove the Superman Boy Scout blinders I've had since I was seven years old.