Marvel Studios President Kevin Feige's first idea for Avengers: Endgame would have seen every member of the original superhero team die.
"Kevin's initial pitch was that it was Toy Story 3 – a 'they're all gonna jump into a furnace together' concept,'" director Joe Russo is quoted in new MCU book The Story of Marvel Studios: The Making of the Marvel Cinematic Universe.
As for why the idea never made it to screen, the book explains: "The [Russo] brothers' pushback was that there was no possible way for the story to be able to take the time to celebrate each one of them. And that, for the fans, it was an impossible scenario to walk out of the theater and process." (H/T Screen Rant)
Ultimately, Endgame had two major deaths: Iron Man sacrificed himself to wipe away Thanos and his army, and Black Widow died so Hawkeye could get the Soul Stone. Thor now has a fourth movie, Thor: Love and Thunder, in the works, while Chris Evans could be returning to the MCU, so it's probably for the best that Feige's idea didn't work out.
