The issue with BvS is simple. It was risky and ambitious. It didn't use the "satisfaction guaranteed" formulaic storytelling.
It wasn't a feel good story - we weren't supposed to feel good. We were supposed to feel agony at the fact that these two heroes had to come to blows and that Batman failed himself, his standards and us. And it was supposed to make us feel pain for all the price of heroism that Superman had to pay. there are great life lessons that are to be learned from BvS. It's just a different form of storytelling that people were not ready for.
They could have just used the formula and everyone will be happy ... I give it credit for ambition. It's a tough thing for artists to contend with.
Synder & the DCEU wont get credit but they have heavily influenced all of comicbook movies. MoS (collateral damage and the heavy consequence of super powered beings on Earth), BvS (hero vs hero fights). Autuers and artists might never get their due because they dont make sugar coated things that everyone likes, but at the end of the day they are the thankless agents of change in industry. They just take the brunt of hurt from being the vanguard.
It's just a different form of storytelling that people were not ready for.
Do you honestly believe that?
That the source material is light and cheery by comparison?
That the story is even remotely original?
The only original ideas here are that Batman is psychotic and brain damaged, that Superman is borderline ******ed and depressed and Lex Luthor escaped from a Looney Tunes cartoon.
Other than that, every aspect of the themes and plot is lifted from existing comic book story lines, just bungled and poorly executed.
There are many, many stories in the source material that are far darker than anything Zack has done, even in the Timmverse, just far more subtle and nuanced than Zack seems capable of.
Although admittedly Zack is the only person I've ever heard claim that his Batman origin would include the prison rape of Bruce Wayne.
There is nothing I actually disagree with in what you stated we were supposed to feel when watching this movie, but the fact that the execution made the intent obvious, yet completely failed to sell it and in many places, completely undermined that intent, is what makes BvS such a poor film, let alone a terrible BvS film and a complete disappointment to the vast majority.
I cannot think of a single scene in the entire movie where there isn't either a failure of logic or failure of characterisation - using the movie's own established internal rules, not preconceived ideas of who the characters should be - so massive that it completely ruins the scene for myself and obviously a great many others.
I could go into detail, but I've done it many, many times already.
The failure of this movie isn't even due to ambition.
It's due to a lack of basic reading and comprehension skills.
Zack was not trying to go darker or be different from the source material.
According to his own statements in interviews, he's giving us a toned down version of Frank Miller's Batman, who he moronically believes "killed all the time" in TDKR.
He's also referred to his Superman as an "amazingly benevolent and kind individual, who grew up in Kansas, which is known for it's niceness", who therefore logically has a problem with Batman's methodology as inherently unlawful.
There's nothing wrong with that idea. It's actually straight out of John Byrne's post crisis reboot MoS in '86.
It's markedly different in execution in BvS.
Many of Snyder's interviews reveal he simply presented what he's found in comics. It's just that what he "read" isn't actually there.
No wonder he's reportedly confused by the critical and general reception to BvS.
He's not being punished for pursuing an alternative vision out of artistic integrity, or a desire to "modernise" or "deconstruct" these icons, but he's merely tried to transpose the characterisations he's misread from the source material.
As he did with 300. And partially with Watchmen, but it's also apparent by the end of that, that he either completely failed to grasp the point of that work, or completely failed to illustrate it.
Of course he's baffled when he doesn't comprehend the difference between his characterisation and his favourite source material.
It's actually quite sad when you examine it.
These characters simply are not believable in any context (outside of mental illness), despite their "burdens".
They are caricatures of human beings, with emotions and thought processes so far from the norm that their behaviours make them pitiable, not relatable.
Certainly not heroic.
I never had the sense once of the terrible burden of heroism, just a sense of how morally and mentally weak all 3 of the main characters were and how little practical intellect the creative team actually must suffer from, to not see the massive flaws they put into the scenes that contain their "cool" ideas.
Superman's grand sacrifice, even ignoring its technical impossibly (within the movies own immediately preceding internal logic), was not a consequence of heroism, but his own stupidity and incompetence.
It was pathetic, not inspirational.
It was analogous to a beach goer who can't swim seeing a struggling swimmer in rough surf, alerting two professional lifeguards, then jumping on a jet-ski to race over and "help", crashing into the drowning victim, killing them and throwing themselves off and also drowning before the professionals could get there.
Tragic, but hardly heroic.
Definitely idiotic.
Great life lesson there.
Trying to prove your bravery by interfering in something you're fundamentally unsuited for, resulting in your own easily preventable death is not brave or relatable but pathetic.
Tragic, not inspirational.
Here's one of the most telling interviews with Snyder I've read:
https://filmink.com.au/2016/zack-snyder-in-depth-on-batman-v-superman/
Once you get past the embarrassing PR, he seems to have a genuine love of the source material and clearly identifies himself as a comic book guy with an infectious enthusiasm for it.
I can easily imagine him selling WB executives on his vision for the DCEU, even Affleck himself, in those terms.
If I'd read this article before I saw the movie, I would have been pumped, despite the couple of red flags in there about Batman being an anarchist and Superman being one simple realisation away from becoming Dr Manhattan.
Then there's this, in defence of a killer Batman;
http://www.heyuguys.com/exclusive-zack-snyder-explains-detail-dark-knight-kills-batman-v-superman/
There's almost nothing he says in there related to the reference material that is even close to being correct.
So no, there is no evidence that Zack has an over-arching alternative take on the DC Universe at all, certainly not a grand one that the world simply wasn't ready for.
All he has is a garbled mess of a story, incompetently adapted from over a dozen classic source material arcs (look at all the Eater eggs), that jaw-droopingly fails any but the most superficial tests for suspension of disbelief.
BvS is not a testament to a vision of the DCEU characterised by an adult themed artistic integrity, but a simple result of and testament to the staggeringly massive reading and comprehension difficulties suffered by Zack Snyder.
As I said above, it's just very, very sad.