Wonder Woman may have played second fiddle to Superman and Batman in Batman v Superman: Dawn of Justice, but in Wonder Woman she's finally front and center. It is officially Princess Diana's turn in the spotlight, which is why it shouldn't be all that surprising for fans to find out that Superman is not in Wonder Woman. Superman's absence from the newest DC film will no doubt disappoint fans desperate for any hints of the upcoming Justice League, but those same fans should take comfort in the fact that Wonder Woman doesn't need Superman's help, not to defeat the bad guys and certainly not to help carry her movie. Superman isn't in Wonder Woman because he doesn't need to be.
The fact that the movie is called Wonder Woman and not "Wonder Woman & Superman" should be a pretty big tip off to Superman's absence. But, then again, so should the events of Batman v Superman and the setting of Wonder Woman. Though the new film is bookended by scenes taking place in modern day, after the events of Dawn of Justice, a majority of Wonder Woman takes place in the early 20th century, long before this version of baby Kal-El crash landed on Earth. It would be pretty weird if Superman showed up to fight in World War I only to re-emerge almost a century later.
As the last DC Extended Universe movie to hit theaters before Justice League, you'd think Wonder Woman might have some superhero crossover to help set up the upcoming blockbuster. However, the ending of Batman v Superman makes it impossible for Superman to be that link. Slight spoiler alert! Superman died at the end of BvS, and thus far he's been absent from the Justice League footage. Nobody really believes that he's dead for good, but it wouldn't really make sense for his big resurrection to take place in Wonder Woman. Not only would it ruin the secrecy regarding his role in Justice League, it would also take away from the glory of Wonder Woman. As the first female-led superhero movie in this modern wave of DC, it would be offensive if the film's title character was upstaged by Superman's big return.
Wonder Woman can carry a movie all by herself, she doesn't need ties to the greater DC Cinematic Universe. Superman's presence is not required, nor should it be. And I, for one, am grateful to see that Wonder Woman got to be the one and only superhero of her own story.