The cut that was released was his cut.
There is no secret cut. He put out exactly what he wanted to put out. Nobody made him edit the movie the way he did. He did that on his own.
Almost every movie ever made has a 3-4 hr cut at one point. It’s usually referred to as the Assembly Cut, and then there are cuts past that point that are sometimes almost as long as that initial Assembly Cut. And all “Assembly Cut” means is “Everything we shot, put it in the edit, and then we can see what we don’t need.”
The same logic that YouTube liars and grifters use to con viewers into subscribing to their channels (“There’s an ORIGINAL cut THEY’RE HIDING FROM YOU”) could have been applied to basically every movie you’ve ever loved. Jaws. Star Wars. Jurassic Park. Back to the Future. They all had super-long initial cuts that had a bunch of story elements that got deleted along the way. It’s not a conspiracy, or evidence of meddling executives. It’s just editing. That’s how stories are told and movies are made.
Sometimes they’re good, and sometimes they’re bad.
I guess Zack Snyder’s Justice League is the only exception to this rule 😃 Back in early 2018, everyone said the same thing you are saying now and they ended up being wrong. I guess since JJ is not saying anything about a JJ Cut, then it probably doesn’t exist. But, we know there were major reshoots and he shot different endings. Obviously, fan editors would love to get a hold of that footage via blu-ray with deleted scenes!