Now, in Just Imagine Stan Lee Creating the DC Universe, his Superman character was from another planet with higher gravity so he was stronger and faster than normal humans. He could fly too, but that's because he had some rocket belt that he didn't tell people about. That character was more plausible than DC's Superman.
Before you say that it's because the Marvel Universe is more plausible than the DC Universe, Stan Lee's Green Lantern got his powers from a talking tree that spewed green gas. And I don't even want to think of the plotline...
So anyway, if Bryan Singer was making a movie about a super-powered being in our world with plausible abilities that can be scientifically explained, that's one thing.
But he made a movie about a comic book superhero who is the most powerful being on earth (unless Darkseid shows up) and can look through girls' panties.
i.e. it's fantasy just like Lord of the Rings.