It's common here in the US as well.
Too add to it:
He's boring, because he's a big blue boy scout.
Right, how could I forget it? Obviously here is the same.
Classic, good heroes like Superman and Captain America are considered boring because they don't kill or use violence. I love such characters, because it's good to see someone that try to do the right thing...
Even if they are only fictional characters, they're a sort of "comportamental model", and I suppose that they can have a greater impact on American readers.
Sometimes, there is who considers them fascists! What a shame.