If Green Lantern can't be a successful movie, then it can't - but this movie was observant and faithful to the spirit and most of the details of the Green Lantern comic.
I think the key is that it's faithful to the spirit of the simple, cornball original
comics. Those are the ones I grew up on, and so I never have a problem when a movie like this (or Superman or Spidey or the Rocketeer) goes for the same kind of simple, cheesy tone.
Of course today's comics are MUCH more intricate and complex, and I get the impression that's what most people expect from the movies as well.
Nah, I still read Green Lantern
from time to time - this movie is right in line with Johns' take on GL, which is not surprising considering the level of his involvement with it. In fact, there's more of his Green Lantern here than there is of the 1960s version.
Nor is there a single way in which a somewhat more successful movie like Thor
can be described as "intricate" or "complex" in its storytelling; the movie's almost schematic in its simplicity, and about as cornball as you can get. So that's not an explanation for the complaints about GL (and of course, you cite Spidey as another example of a movie with a "cheesy" tone, and its popularity humbles all but Nolan's Batman
and maybe Iron Man
in its success - every other superhero movie is trailing those three by a long distance now).
Of course, there were comparisons between Star Wars
and GL, in terms of the scope and tone, before it was released - and that might not have been a good model for them. If a space opera movie with the broad tone, goofy humor and heavy-handed dichotomy between the good and bad characters that Star Wars
is memorable for were released now, it'd likely be savaged.