Rosenbaum's portrayal of Lex Luthor was a crucial part of Smallville, offering a deep and evolving character that shaped Clark Kent's journey. Over seven seasons, Lex transformed from a complex companion to Clark into his formidable adversary, blending intelligence, charm, and ethical ambiguity.
During the Crisis on Infinite Earths crossover, Tom Welling reprised his role as Clark Kent, but Rosenbaum's Lex was absent. While Jon Cryer delivered a compelling performance in the role, fans missed the chance to see Rosenbaum's Luthor interact with other versions or join the Anti-Monitor as depicted in the comics.
Similarly, Linda Carter, an icon as Wonder Woman, who helped define female superhero representation, made a brief cameo as President Marsden in the Arrowverse but was never seen as Wonder Woman during the Crisis crossover. This omission was especially felt given the importance of Wonder Woman in the comic storyline.
Helen Slater, known as 1984's Supergirl, now plays Kara's adoptive mother in the Arrowverse, was another missed opportunity. In the comics, Supergirl plays a crucial role by sacrificing herself, something that could have added depth to the crossover if woven into the Crisis narrative.
Dean Cain, best known for his lighter and romantic portrayal of Superman in Lois & Clark: The New Adventures of Superman, was also absent in the Crisis event. His inclusion alongside other versions of Superman could have showcased the diverse portrayals of the character.
Meanwhile, though we saw members of the Titans, Brenton Thwaites' Nightwing was notably missing, as Thwaites chose to keep the character separate. Nightwing embodies the progression from Robin to an independent hero and could have contributed a youthful, gritty angle to the crossover.
The Arrowverse's Crisis on Infinite Earths brought many memorable moments and cameos from DC actors, but the absence of these figures left a noticeable gap in representing the franchise's legacy. Whether due to logistical reasons or conflicts, their presence would have added another layer to the multiverse.