Zack Snyder's Justice League was widely hailed as superior to Joss Whedon's theatrical cut. Despite this, many audiences took issue with the film's whopping four-hour runtime. And so, one has to wonder what scenes might've been left on the cutting room floor if Zack Snyder still directed it in 2017.
After Whedon took over as director of Justice League following Snyder's departure, he fulfilled the studio's strict demands to compress the film to two hours, leading to extensive reshoots that ultimately ruined the movie for most. While Snyder finally got to release his four-hour cut of the film four years later, a movie of this length wouldn't have been released in theatres and would've been trimmed down to at most three hours. With that, there are multiple scenes in this film that could've been left out, at least for the theatrical cut.
Flash Rescuing Iris
One particular criticism fans had of Whedon's Justice League was how it cut out multiple characters of color, including Kiersey Clemons' Iris West. Nevertheless, the scene in which her character is rescued from a car crash by Barry Allen didn't add much to the main plot and could've worked better in the Flash's solo movie.
Though it does give the audience a closer introduction of Barry's powers and character, the film could've still successfully done that with the scenes of him visiting his imprisoned father and meeting Bruce Wayne. Also, the way Barry touches Iris's hair without her knowing while using his super-speed came off as kinda creepy to some audiences.
Both of Martian Manhunter's Scenes
The film's reveal that Harry Lennix's Colonel Swanwick was Martian Manhunter in disguise was a shocking twist for many a fan. However, some complained that this scene somewhat detracted from the heartfelt scene between Lois Lane and Martha Kent over Superman's death, having been revealed that Martha was really Manhunter trying to help Lois.
Likewise, if Martian Manhunter's conversation with Bruce were to be cut from Zack Snyder's Justice League, the filmmakers could've saved this twist for the future. Without this epilogue scene, the earlier twist would've been out of place in the film, leaving too many lingering questions for the audience. It also wouldn't have worked vice versa, as Harry Lennix starring as Manhunter would've given away the twist behind his character's identity as Swanwick.
That Icelandic Song For Aquaman
After Bruce meets Arthur Curry, the latter refuses to join his Justice League and returns to the ocean. As he leaves the Icelandic town he watches over, some of the locals sing a beautiful song that's meant to convey how they see him as their protector. Despite this, the way the townspeople try to keep Arthur's identity as the Aquaman a secret already succeeds in depicting this, so this extraneous musical sequence could've been cut out of Zack Snyder's Justice League.
Diana Entering the Shrine
After Steppenwolf steals a Mother Box from the Amazons, Diana's mother, Hippolyta, shoots an arrow across the sea and into the Shrine of the Amazons, creating a fire that warns Diana of this alien invasion. Even though her exploration of this shrine shows her learning about Darkseid's invasion through an ancient and foreboding mural, it could have still been removed from the film. Audiences could assume she already knew that this fire was signaling Darkseid's return, given her extensive knowledge about the Amazons and their history on Earth.
Superman Meeting Alfred
This scene was Superman's first face-to-face encounter with Bruce's butler/caretaker, Alfred, before he goes to fight Steppenwolf. Even though it is a nice and rare conversation between these two characters, it still doesn't really add anything to the story.
Superman may have needed Alfred to explain the situation with Steppenwolf or to help locate the villain's lair. And yet, Superman doesn't actually need an explanation since he just had to help his friends and stop the alien threatening Earth's future, especially when the clock was ticking. At the same time, Superman could still just locate Steppenwolf and the Justice League with his super-hearing, so this scene remains unnecessary.
The Hypothetical John Stewart Scene
Snyder has gone on to say how he originally planned to have the Green Lantern, John Stewart, meet Bruce at his lakeside house at the end of his Justice League instead of Martian Manhunter. If Snyder still directed the film in 2017, he could've gotten his way, but that doesn't necessarily mean it should've been included. The scene in question serves to introduce Stewart and have Bruce learn that Darkseid still threatens Earth, but the film already demonstrated that with the alien tyrant looking down on the heroes through the Boom Tube after Steppenwolf's death.
Everything after Superman revealing his 'S' at the end of Justice League could've been used as post-credits or mid-credits scenes in theatres. But with the introduction of Lex Luthor and Deathstroke's alliance and the Knightmare scene with Joker, adding this final conversation might've been too much.
Knightmare With Joker
Speaking of the Knightmare, given that this scene was filmed during the pandemic, it's unclear if it would've been made four years ago. While this could've been a great post-credits scene to end the film with, unlike Bruce's lakeside meeting, it's unknown if it was even an idea back when Snyder was still directing.
The mesmerizing interaction between Batman and Joker explains how the former letting Lois die caused this post-apocalyptic future to occur. Nevertheless, Justice League already placed little hints of that, explaining how Lois was "the key" to Superman. Plus, the image of him holding her charred corpse was enough to imply that her death drove him to Darkseid. All in all, this scene could've worked just as well as a conclusion to Snyder's planned sequel to Justice League, which would've taken place five years after the heroes lost to Darkseid.