When Avengers: Infinity War ended with such a bang, we were all left with a lot of questions. Once everyone had stopped crying and wondering what the hell the point in even living was any more, attention was turned to Endgame and speculating on how those questions might be answered.
We got answers to how the snap would be undone, how the timeline wouldn't be destroyed by time travel, how the Quantum Realm would be important after so much teasing and all manner of other delightful confirmations. But there's always been a bit of a niggling concern for some fans.
Here's the thing: while we knew that Doctor Strange's ability to see into the future thanks to the Time Stone was pretty crucial to Tony Stark making his grand heroic last stand and saving the universe, it wasn't entirely logical. After all, as the Ancient One had established in Strange's solo movie, foresight couldn't go beyond the point of the seer's own death. It was a pretty crucial moment that underpinned what was genuinely a tragic moment for the character as she was forced to face the immediacy of her mortality.
While Strange saying he knew that there was only one future where the Avengers won - which all depended not on the mouse standing on that button, but actually on Tony Stark choosing to kill himself for the Greater Good - meant for certain that the Snap would be undone, it confused the logic established by the Ancient One previously. After all, Strange might have been seeing alternate futures, but they all happened beyond the point of his "death" at the end of Infinity War, so he shouldn't have been able to see them.
He might have come back, but he came back FROM THE DEAD, so the logic never worked.
And it seems the writing team knew this was a bit of a problem, because a deleted scene for Endgame has emerged on Disney+ that clarifies exactly how it was possible, as well - crucially - as explaining how the Snap actually worked.
Up to now, we've all sort of operated on the idea that the Snap was simply a magical event made possible by the unfeasible power of the Infinity Gauntlet. That Thanos effectively just made a super-weapon capable of unprecedented universal destruction. Sure, there were intricacies, like the Power Stone acting as the "battery", the Mind Stone focusing on all of the individuals targetted, the Soul Stone being the mechanism for changing their existence from living to dead, but none of that was explicitly stated and we all still assumed that the victims were simply all killed, no matter how it happened.
But this deleted scene changes everything. In it, we see a different version of the rooftop conversation between the Ancient One and the Hulk, which reveals not only that she was able to foresee the Snap but also that what Thanos does is not actually kill his victims. The key distinction is that Thanos actually WILLED people out of existence.
That explains why Strange was able to see the future beyond the point of his death - because there wasn't an actual death event.
Could this suggest that there might be a way to return Tony Stark from the dead? Could this be the key to how Black Widow has been rumoured to return for more movies even after her own death in Endgame? That last question is more complex, since she wasn't killed by the Snap, but it would offer an opportunity for the writers to write AROUND the firm logic of death at least. It's an intriguing prospect.
It might seem pedantic, but it's definitely a crucial difference and it answers one of the most persistent plot holes in the entire movie. It's a shame it was left out, but it's far from a flawless scene and the final version is superior. You also have to wonder whether the audience would have accepted quite so much handy exposition all in one scene.
And part of its flaws is that it doesn't quite fix the plot-hole, after all. Because the Ancient One manages to talk about events that would occur after her own death - such as the Snap - despite the fact that she categorically DID die. There was a way to write around that, but the alternate scene didn't find it and that might well be why it was cut.
Anyway, regardless of the problems, it's good to have that answer - or at least to know that it would have been addressed partly in one version of the movie.
You have to wonder what being willed outside of existence actually looks like. The survivors who returned didn't express any sort of memory of their time after the Snap, but that doesn't mean they weren't even subconsciously aware. The distinction of them not being dead seems to suggest that there is potential - like with the Civil War comic that killed Captain America and then retconned his "death" to being him sent somewhere between time and space - for Stark to be out there somewhere still.
And while the ending of Endgame was arguably the perfect end for Robert Downey Jr's character, Marvel Studios would be idiotic not to entertain any ideas that could bring him back - even temporarily - in the future. After all, that's the kind of idea that money is made of.