At first, Chris Evans turned down the chance to play Steve Rogers (Captain America). Kevin Feige, the MCU producer, was still set in his ways and knew precisely what he wanted for Captain America. Chris Evans said on Jimmy Kimmel Live that he turned down the chance to be Captain America at first because of his anxiety, but Kevin Feige pushed him to take the role.
When he was cast, Evans wasn’t as well-known as the other actors around him. Evans had been in the Fantastic Four and Not Another Teen Movie with famous actors like Scarlett Johansson, Mark Ruffalo, and Robert Downey Jr. Still, nothing in the MCU was as good as what he was used to.
People already knew who Downey, Scarlett, and Mark Ruffalo were at the time. Since Chris Hemsworth also had it, he was a welcome guest. We were both very inexperienced and the only ones acting on our own. So I think this made us more worried about each other.
We got the Captain America we know and love because Feige fought for him. Still, by talking so much about his Anxiety Issues, Evans helps make worries that many of us try to hide more acceptable.