As the years went on, it felt more and more like Cyborg was something of a “diversity hire” for the latest incarnation of the Justice League. When it came to the big stories, he didn’t really seem to have any purpose beyond getting hijacked so his tech powers could be used for the bad guys, as was the case with Forever Evil and the creation of his evil counterpart Grid. If he wasn’t experiencing that, he was grousing about whether or not he was a man or a machine, a dilemma that long ago stopped being interesting. Not to mention that he was the last member of the Justice League to get a solo book; Batman, Superman, Wonder Woman, Flash, Aquaman and Green Lantern (both Hal Jordan and his successor, Simon Baz) had solo comics right out the gate when the reboot began. That’s not a good look, especially considering his first solo comic also didn’t come until the New 52 was pretty close to being done.
He was a character DC wanted to elevate into the big leagues, but haphazardly. In wiping away the canon of everyone in the New 52, DC also wiped away any real justification for Cyborg being on the Justice League beyond convenience. Cyborg is defined in part by his relationships with those he cares about, as a big brother to the other Titans like Raven and Beast Boy. But in the League, he doesn’t have anyone he can be that big brother to, as they’re all support systems for each other in some way. And since he also lacks a truly defined supporting cast like his fellow Leaguers, he can’t help but feel like walking tech support.
With his solo movie not due for another three years, Justice League and Teen Titans Go will offer the definitive versions of the character for those who don’t read comics. And given how much goodwill the DCEU still has to build with the wider audience, it’s safe to say that TTG Cyborg will continue to win that battle. Say what you will about Teen Titans Go, but the show's interpretation of Cyborg has managed to enthrall fans since his introduction. That version of the character is brimming with personality and has done a lot more for his reputation than comics really have for the last five or six years. If you asked a kid what they know about Cyborg, it would probably involve how he shouts “Booyah!” and loves “The Night Begins to Shine,” traits that are likely going to define him for years to come.
Cyborg is in the precarious position that many comic book characters are these days -- he's been boosted to a higher media presence, but it's one where his resulting level of popularity will depend on how much justice the movie does the character. This isn't a problem other Leaguers such as Flash and Aquaman have -- the Scarlet Speedster has four years worth of a TV show for fans to look to if they're unhappy with Ezra Miller's version, and Jason Momoa is... well, he's Jason Momoa, and no one will really be unhappy with his take. Ray Fisher is another story entirely, as this'll be his first big role. And that's why Justice League needs to get both the actor and character right; their futures depend on this film more than most.