There's a big difference between social activism and Anti-heroes with feet of clay. You make a great point, was Golden Age Superman at odds with local law enforcement? Did the media ever try and turn the people against him? Not that I can recall. It seems to me that these concepts were so fresh to Spider-man in the 60's because we hadn't seen them in DC comics before to any great extent. But in order to rationalize bastardizing Superman's character, his history gets revised in the mind's of some people.
Where is the social crusading in that was advertised in AC Nu anyways? After the first half of #1, that's over with and Clark starts working through Peter Parker's checklist:
Authority is out to get him
he's not fully matured physically or emotionally
the media turns the public against him
its not easy being a hero
he's even got a pseudo Aunt May in his landlord, watching his back.
I think the only thing worse than Superman's cliched existence is someone else's.