Naturally this all changed with the arrival of the MCU. It's hard to describe how much of a game changer this proved to be, how greatly Marvel Studios managed to pull off just the right combination of 'faithful to the source material' with 'won't alienate non-comic readers'. Characters like Iron Man and Thor were suddenly household names, to the point where Tony Stark nearly replaced Spider-Man as Marvel's poster boy. Within a handful of years Marvel was now the name in superheroes, and it was DC trying to play catch up.
It really should have been a slam dunk for DC. Marvel had already laid out the groundwork for how to pull off a successful shared universe. DC already had a history of successful superhero films that normal people could enjoy. Batman's film success showed that it could be done, though with films like Superman Returns, Catwoman, Steel, Green Lantern and Jonah Hex (as well as the third Nolan Bat-Film IMO) showed that their track record wasn't perfect.
Still, if they approached a Cinematic Universe the way Marvel did, if they got creators that cared about the source material, had a genuine love for the characters, could get actors invested in maintaining these roles for as long as possible, and drawing on their experience with successful superhero film and television, DC should have been a major competitor for Marvel's dominance of the Superhero Film industry.
Should have been. We all know that it didn't work out that well.
Man of Steel was demolished by Iron Man 3 at the box office that year, and in fact only managed to roughly tie Iron Man 2's numbers despite that movie having come out 3 years earlier. Thor 2 matched Man of Steel's box office. And the following year, both Captain America: Winder Soldier and Guardians of the Galaxy likewise surpassed Man of Steel's box office. The film with the talking tree got more repeat viewings than Superman.
When Batman v. Superman came out, its figures improved, but it didn't approach Avengers numbers and, in fact, was only moderately more successful than the first Guardians film. Wonder Woman's solo film did roughly as good as the first movie featuring Batman and Superman together on screen for the first time, and AQUAMAN did better than either Batman v. Superman or Wonder Woman. Even when Justice League came out, it couldn't touch the Avengers films and was roughly as successful as the Suicide Squad movie. The Shazam film made less money than ANT-MAN, though it looks like the Harley Quinn film film is set up to be the lowest grossing DCEU film yet.
Meanwhile the most profitable DC film of the last decade was The Joker film, which only grossed a little less than Aquaman but cost much less to make.
Let that sink in: in an age where Batman and Superman met on screen, it was the historically mocked Aquaman having a fun adventure and a depressing, deconstructive film about Batman's arch nemesis that made the most money.
So what happened?
There have been several explanations made, many of them making sense. It's said that the behind the scenes problems prevented the kind of cohesion a Cinematic Universe needed. It's said that Warner Bros. wanted Avengers money without putting in the time and effort to properly world-build a Cinematic Universe, and it's rushed nature lead to poor decisions and a disjointed feel. It's been said the people making those movies weren't as passionate about the DC characters, and thus didn't have the same investment. And I think those reasons are all true to some extent, as well as other reasons being the issue.
But the core problem I see with the DCEU was that it was flawed from its inception. Zack Snyder was perhaps the worst pick to do a superhero setting built around the likes of Superman, Batman and Wonder Woman, save for someone like Rian Johnsen. The guy just fundamentally does not understand what makes the DC heroes tick, barely understands what comic book superheroes are suppose to be. And here's why:
Zack Snyder is a proud cynic in a setting primarily based on optimism. It makes complete sense why he would introduce Superman as a person consumed by fear, why he would focus on hyper violence that gets people killed, and why he'd end the film with Superman snapping his opponent's neck. It makes sense why Zack would have BATMAN killing people while committing THEFT, how Zack could create a film where two of the greatest heroes in history are fighting and no one is rooting for either of them, and how Zack would accidentally make Wonder Woman the most popular character in a Superman vs Batman film.A Reddit video shows the director answering questions at a charity event screening director's cuts of several of his films. At the Q&A for Watchmen, Snyder explained how that film colors his work and should influence how it's understood. He used the example of Batman killing, saying, “Someone says to me: [Ben Affleck’s] Batman killed a guy. I’m like, ‘Fuck, really? Wake the fuck up.'"
Snyder then went on to talk about how Watchmen differs from other superhero movies. "I guess that’s what I’m saying," he continued. "Once you've lost your virginity to this fucking movie and then you come and say to me something about like ‘my superhero wouldn’t do that.' I’m like ‘Are you serious?’ I’m like down the fucking road on that. It’s a cool point of view to be like ‘my heroes are still innocent. My heroes didn't fucking lie to America. My heroes didn't embezzle money from their corporations. My heroes didn't commit any atrocities.' That’s cool. But you’re living in a fucking dream world.”
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The DC Extended Universe was NEVER going to be the Marvel Cinematic Universe, because it was built on rotten foundations. The rot just continued to spread, and the only films that did genuinely well were the ones that rejected Snyder's sensibilities and embraced actual fun heroism like Wonder Woman and Aquaman. It's sad when the frickin CW universe feels more like DC than the DCEU.
There is no hope for the DCEU. Warner Bros. needs to take some time to just let it die, give fans 5 years to forget about it and let Marvel experience MCU burnout. Spend those 5 years really planning out and developing a unified setting closer in tone and feel to something like the Justice League/JLU cartoon. Have heroes that actually look and act like their classic counterparts. Have films that are inspiring and not destructive and deconstructive. And for the love of Highfather, make these movies FUN.