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This kind of confuses me... Taking a stone from a timeline disrupts the said timeline right? While getting a person FROM a timeline seems no repercusion (E.G Loki vanishes with the Tesseract(Space stone), 2014 Thanos comes to present)
Why can't they just get a Tony Stark from the past, maybe before the snap? Or maybe alter the whole History (Make Captain Marvel snap the gauntlet rather than Tony, she held the gauntlet for some time right?)
Just so that Stark can have his family and the whole movie wont have to have a sad ending.