Then, in the Avengers: Infinity War films, Tony Stark will prove himself and have a triumphant farewell, while paving the way for a new younger superhero to take the reigns of the Marvel Cinematic Universe.
That could involve him saving the day and moving off into the sunset, or it might involve Marvel finally killing off someone of importance.
In fact, I believe that Spider-Man: Homecoming will set Tony Stark up as an aging superhero that’s little past his prime, something that was teased at Civil War.
I think it will probably be the former, because that would leave the opportunity for the Marvel Cinematic Universe to turn to Downey in a supporting role if they ever actually hit some trouble.