There’s an argument to be made that Tony lost his life due to miscommunication. When he looks at Dr. Strange, he sees the Doctor holding up one finger, signaling him that they’re currently in the exact timeline where they won. If only Tony did what the Doctor was thinking, he would’ve been A-OK.
But noooo. Instead, Iron Man snatches the Infinity Stones away from Thanos and uses the snap of doom to get rid of the army of bad people, which is the ultimate sacrifice on Tony’s part. But what if, and hear us out here, Dr. Strange meant for Tony to use one of the Infinity Stones against Thanos? Nope, dying is more dramatic.