It's funny how the tides of narrative shift. When Batman v Superman came out, the poor reception led to Warner Bros rethinking their entire approach to comic book films and making large-scale changes to their intended slate. The blame - because we have to live in a binary world of extremes where there MUST be one person to blame - lay, apparently, at the feet of Zack Snyder.
It's not hard to see why it happened - Snyder had spoken publicly about his reluctance to ever make a "normal" comic book movie when he was making Watchmen and his obvious fascination with deconstructing established tropes was an easy stick to beat him with. We could call him a betrayer of lore and source material and point to where he said he didn't even like Superman.
But then, quietly, Snyder redeemed himself for a lot of fans by releasing a director's cut of Dawn Of Justice that wasn't just better than the theatrical cut, but vastly superior. It was like he was working unshackled and this was his true vision and it worked. So it's strange that Warner Bros then slapped the shackles back on him and tightened their grip on Justice League, adding creative requirements and limits on Snyder's vision from day one and then seemingly changing them as a reaction to what he was making.
4. The Background
Like Tim Burton before him, Snyder's vision was just too dark for Warner Bros. They had aspirations to make a financial behemoth in the vein of the MCU and to continue selling lots and lots of lovely merchandising licences for Batman - the same reason Burton was so unceremoniously shunted out of Batman Forever, despite Batman Returns' successes. Their manifesto is one of money, not of creative vision and what they saw in Snyder's original take on Justice League was financial disaster, so they took drastic measures.
First, they told Snyder to change his first cut and the result was something that was deemed "unwatchable" by the studio. Then, as Snyder faced an unthinkable family tragedy, they took things further, replacing him with Joss Whedon - a man so well-versed in the MCU's pillars that he'd basically built some of them himself. His agenda was to lighten and tighten, refilming things, cutting others and bringing in an entirely different tone. He was given an unenviable task at best and an impossible one at worst.
And then the film came out and it was a monstrosity that underperformed badly at the box office and led to yet another critical mauling. With the injustice of what had happened to Snyder - not least because of his family's tragedy but also because he had PROVEN with the Director's Cut of BvS that he was capable of delivering - fans took up the cause to get his fabled first cut - the Snyder Cut - out into the world. We all deserved to see it, clearly, and Snyder deserved to be given the chance to let his vision out.
The question, for two years, though, has been what that vision actually was. Would it have been worth seeing? Would it have outperformed the theatrical cut? To answer that, we have to examine exactly what Snyder would have included that Whedon didn't and the directions his replacement took that he simply wouldn't have.