Zack Snyder has been known as someone that sticks to his guns and his vision no matter what, and that certainly appears to be the case here. Additionally, he appears to be keeping up with his tradition of revealing most of his plans for the DCEU, especially since the Snyder Cut will likely be his final run with the franchise.
In a recent chat with the New York Times, director Zack Snyder spoke on what his plans would have been if he had continued with the DC Extended Universe. Specifically, with future Justice League movies, the armies of Earth would have all united again “when Darkseid comes to Earth,” coming to the aid of “Atlanteans rising out of the ocean and the Themyscirans coming off their island” to fight the DCEU’s big bad.:
It’s the fall of Earth, when Superman succumbs to anti-life. And then sending Flash back in time to change one element so that doesn’t happen. And then the big battle where we beat him. When [the villain] Darkseid comes to Earth, in the movie that you’ll never see, the armies of Earth all unite again, as they did before. This time there would be aircraft carriers and Special Forces guys, all the armies of the world would come together, as well as [Aquaman’s fellow] Atlanteans rising out of the ocean and the Themyscirans [Wonder Woman’scompatriots] coming off their island. That was our big finale. But it’s a long drum roll and guitar solo to get there.”
In terms of this new version of Justice League, Snyder was also asked why the film ends on a cliffhanger rather than having the story come to a definitive close. Snyder simply explained that “The ask was for (his) version of the movie” when it was approved for production.