When the DC Extended Universe launched with 2013's Man of Steel, the movie featured a new darker take on characters like Superman that laid the groundwork for the shared universe, though the change in tone was quite a departure from the previous franchise of films starring the Last Son of Krypton.
Superman: The Movie hit theaters in 1978 and introduced fans to a serious but light-hearted take on the character that made viewers "believe a man can fly." However, with each new sequel (Superman IV: The Quest For Peace released in 1987), the franchise featured increasingly silly moments that became tragically unforgettable and would never have worked in the current DCEU.
Revolving Door/Photo Booth Costume Change
The original Superman adapted a number of iconic moments for the character, which included a take on his classic phone booth costume change that became tied to the character after the Max Fleischer animated shorts.
Superman used a revolving door to accomplish a similar effect in the first movie and a photo booth in the fourth, but would still be unlikely to be seen in the modern DCEU. Not only are phone booths largely a relic of the past, but the realities of our modern high-tech camera-filled society makes those kinds of quick public transformations far too dangerous for secret identities.
Night Flight With Lois
Superman and Lois's first flight together is both memorable and romantic, but it's also fairly silly when viewed through a modern lens, especially with Lois's poetic inner monologue as they soar through the air.
The scene was even hilariously lampooned in 1991's Hot Shots! parody, which only brought out the inherent comedy of the original scene. Modern Superman adaptations like Superman Returns and Man of Steel have homaged the scene in various ways that have removed the camp but kept the romance.
Otis/Lenny Luthor
While clumsy comedic henchman continues to be a staple in any comic criminal organization, the grounded and realistic movie adaptations from the DCEU don't make it easy for those kinds of characters to succeed.
The original franchise featured a pair of lackluster lackeys that were added for their comic appeal, with Ned Beatty's Otis appearing in the first and second Superman adaptations. Jon Cryer would portray Lex Luthor's bumbling nephew Lenny Luthor in Superman IV, though his later role as Lex in Supergirl was a far cry from Lenny.
Turning Back Time... Twice
The original Superman may have featured a dramatic and serious climax with the apparent death of Lois Lane after a cataclysmic earthquake buried her car in the rubble, though it quickly turned into a ridiculously unscientific moment that fans would tear apart in the DCEU.
Yelling in despair after losing Lois, Superman flew at super-speed around the planet until it started to spin backward, somehow reversing time and undoing the damage. He did this again in Superman II: The Donner Cut to undo the events of that movie as well.
Super-Breath Fight
After an explosive battle in Metropolis between Superman and the escaped Kryptonians from the Phantom Zone in 1980's Superman II, General Zod and his allies united to take down Superman with their combined Super-Breath power.
While it's undoubtedly a powerful ability, the scene featured a number of comic bits (later removed for The Donner Cut) that included ice cream flying into a bystander's face while cars are also being thrown across the street by the same force. Uneven and out of place for such a large battle, which also wouldn't fit in the Man of Steel style of movie.
Silly Super Powers
The original franchise took quite a few liberties with Superman's abilities beginning with Superman II, which began a comedic departure for the franchise by new director Richard Lester after Richard Donner was let go from the franchise.
Superman II featured unexplained duplication/reflection tech in the fortress, a giant plastic "S" shield trap thrown from his costume, and random laser finger blasts from Zod. Superman has always had vision-based abilities powers, but those powers were stretched in Superman III when he used his vision to repair the damaged Great Wall of China.
Super Amnesia Kiss... Twice
Another unexplained and somewhat ridiculous ability that would never work in the modern DCEU was first introduced in Superman II after Superman and Lois realized they couldn't stay together and shared a final kiss.
The kiss turned out to be a memory-erasing super amnesia kiss that made Lois forgot about Superman's secret identity and helped return things to the status quo, instead of the Donner Cut's repeat of the time-reversal. The super kiss was repeated in Superman IV after Clark revealed his secret to get advice from Lois, then promptly wiped her mind again.
All of Superman III
While the DCEU has introduced more comedic moments into the shared universe with films like Shazam!, the silliness of Superman III is still on another level that separates it from the rest of the original franchise. Comedian Richard Pryor played a central role in the film that included outlandish gags like accidentally skiing off of a skyscraper ski slope and landing perfectly on the street.
The opening credits of the film featured a slapstick morning in Metropolis that would have fit in a Naked Gun film, and a climactic battle with a randomly robotized villain created by an impossible computer designed by Pryor's character Gus Gorman, who had just finished computer programming training.
"Advanced" Computer Technology
Pryor's role as a computer programmer began as an interesting look at the unemployment situation in America at the time but quickly turned into an uninformed look at new computer technology as a villainous tool that was masterfully manipulated by first-timer Gorman.
However, little of what is done with the computers in the film was ever possible or made much sense, making it laughable to today's more knowledgable audience. Some of the sillier moments include the new corporate villain operating the computer's defense systems through a video-game-like interface that was hard to believe back then, let alone in today's DCEU.
Superman vs. Nuclear Man
There were quite a few silly moments in the final film of the Superman quadrilogy, though most of them involved the character of Nuclear Man, who was created for the movie using an altered take on Bizarro's comic origins.
aThe reduced budget of Superman IV: The Quest For Peace led to poor fight scenes with ridiculous moments that included Nuclear Man flying around with the Statue of Liberty before randomly dropping it, and a fight on the moon where Nuclear Man pounded Superman into the ground and then covered him with moon dust as if it was kitty litter.