I disagree to the extent that it was a Superman movie in world where these other characters exist rather than a DC movie. We didn't interact with the characters unless they were related to what Superman was doing, e.g we didn't see the fight with the interdemensional imp aside from it being a background to Superman and Lois convo.After taking time to think on it, i actually think James Gunn did a decent job here, The humor wasn't too overdone like with the Guardians.
The major flaw with this movie though, was the same flaw most people had with Iron Man 2. Movie doesn't stand on its own. Feels like it was designed to tease future projects instead. Wasn't a superman movie. instead it was a DC movie superman ass the lead. this was designed to make you wanna watch, Supergirl, justice league, MR Terrific and whatever else. (apparently Jimmy Olsen is getting his own spinoff from this too.)
If you complained that black panther took a backseat to the rest of the cast in his first movie. You should feel the same way about this one. Superman got his ass beat for 90% of the movie, was even captured and sidelined for a good 20 minutes of the film so another character could get his moment to shine. James Gunn claimed in interviews that he didn't need to see another origin story for superman. I understand that was a statement made purely for financial reasons now. He didn't want to do that because he wanted to be able to tease for future dc projects. I would be interested to see the next one focus more on superman next time. Because outside of that everything else worked for me.
We can say it was used to tease future projects, but if the characters were ignored, we have to then hand wave in future movies where the hell were they when the kaiju was attacking Metropolis

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