At the end of Avengers 4, it is sad to say that Chris Evans contract from Marvel will be up and that could be the end of Captain America in the MCU. However, Evans has said that he is “open” to doing more Cap movies to Collider but it depends on whether Marvel is up for that as well.
Even if Evans does not return for the iconic role I doubt that that would be the end of Captain America in the MCU. I don’t think Marvel would recast the character because Evans has done so much for the character that it wouldn’t work if they just threw a new actor into the role of Steve Rogers. What’s more realistic is that they would simply pass on the mantle of Captain America to someone else. Marvel does have a few options that are already in the MCU.
Since the introduction of Sam Wilson, and I guess you could say re-introduction of Bucky Barns as the Winter Soldier, it seams that Marvel might go in the direction of giving one of the two the role of Captain America. In the comics both Bucky and Sam have carried on the role so it makes sense to why Marvel brought both these characters into the movies. In Civil War. We saw a couple scenes with Bucky and Sam alone and there is clear tension between the two because they both see eachother as Rogers best friend. Okay so let’s just say that at the end of Avengers 4, Captain America is killed by Thanos and Sam and Bucky both survive. What happens then? Being a super Marvel fanboy like I am I would love to see a conflict between the two for the mantle of Captain America. Personally I think Sam would be better in the role because he has the Falcon suit still and he is a total badass in the comics.
If this truly is the end of Chris Evans as Cap at the end of Avengers it would still leave a hole in that character because Evans has been such an amazing Captain America and I don’t think anyone could play the role as well as he has. Captain America: The First Avenger was one of the first Marvel movies I watched so it will always be close to me. The people at Marvel are cinematic geniuses though so I trust that they will do the character justice no matter who’s playing it.