In Avengers: Endgame, during the short time that Scott explains to Steve and Natasha that he was stranded for the last 5 years in the Quantum Realm, he really only shares info about the Quantum Realm that is necessary to Endgame’s story. Even Scott’s reunion with his daughter is cut down to a minimum in order to address the looming question of where his daughter is, without spending any more time than necessary developing a side story that won’t further develop the film’s main plotline.
In a new article featured on Marvel Entertainment’s website, Ava Starr, aka Ghost, and a recap of her MCU backstory from Ant-Man and the Wasp are given the spotlight. The article seems to indicate that Ava’s story in the MCU may not be done yet, hinting that she’s “on her way to being known as friendly,” despite her misunderstood yet devious intent in her MCU debut.
“After Janet Van Dyne is rescued from the Quantum Realm, she can sense Ava’s unstable state and is able to partially heal Ava with some of her own quantum energy. Scott eventually goes back into the Quantum Realm to collect quantum healing particles just for her, which of course was mere moments before the Blip happens and he gets stuck there for five years, but that’s a story for another time.”
The most interesting point in the article, though, is where the writer makes quick mention of Scott Lang’s time spent in the Quantum Realm between the events of Infinity War and Endgame, and how the events that transpired are “a story for another time.”
This single sentence about Scott’s trip to the Quantum Realm being a story worth telling later on cracks open a whole new world of speculation for what the MCU’s future may look like.