2) Robert Downey Jr.
Actually, scratch what we were just saying about Wolverine being the superhero most associated with one actor. If you ask someone ‘who is Iron Man?’ they will most likely answer ‘Robert Downey Jr.’ instead of ‘Tony Stark.’
However, Downey Jr. was largely seen as a wildcard casting choice before he blasted onto the screen for the first time in 2008’s Iron Man. The actor had famously had his ups and downs and people weren’t sure if RDJ, who had never before been box office gold, would be able to carry a superhero franchise on his shoulders.
Nowadays the story is reversed and RDJ is the most reliable player in the MCU, having starred in half a dozen hugely successful films as Iron Man. There is surely no one left in the world who thinks the actor is a poor fit for Tony Stark.
Like with Jackman, the franchise will have a hard time replacing him when he eventually bows out.