It's obvious! Stan has a nine picture deal AND Chris Evans is "retiring" after his contract expires! That means Sebastian Stan's Winter Soldier A.K.A Bucky Barnes will take the mantle of Captain America, right? One thing Marvel Studios is GREAT at doing is making us, the fans, think we have it all figured out. We thought we figured out that Thanos HAD to be the villain in Avengers 2. We thought we figured out that Iron Man was gonna fly into space to meet the Guardians of the Galaxy at the end of Iron Man 3. We also thought we KNEW that Doctor Strange was gonna go up against Batman and Superman on May 6th, 2016 but it seems that is incorrect as well. My point is, is it really THAT obvious? Thanos in Avengers 2 was right? Here are some specific reasons why I think Bucky will NOT become Captain America in the MCU.
1) THIS ISN'T THE COMICS If Iron Man 3 is an example of anything, Marvel Studios isn't directly pulling stories from the comics and putting them on the big screen. Yes, they are the characters in the comics and there are easter eggs thrown in for fans, but not everything in the comics translates well in movies. Watchmen, for example, did a great job making a near shot by shot movie based off the beloved graphic novel and for the most part, fans loved it. However, this didn't appeal to the modern moviegoer as much as it did the fans. Marvel has done an excellent job at making their characters more mainstream. I understand that this is a fantasy world, hell, I can accept Coulson coming back to life on TV with some crazy robot, alien thing or however he came back, but Coulson's resurrection wasn't a movie worthy story. Marvel could easily make Bucky into Cap, but how would the everyday moviegoer react to this? They would be confused because Marvel made Steve Rogers mainstream. Im not saying Rogers won't die in future movies, but people who aren't comic fans, who just watch the movies, KNOW that Steve Rogers is Captain America, just like they KNOW that Peter Parker is Spider-Man. There have been other alter-egos to these characters but the movie fans won't know that. Bucky becoming Captain America was a great story in the comics but I don't think it will translate well to the modern movie viewing audience.
2) STAN'S CONTRACT MEANS NOTHING Again, people think they have it all figured out. Sebastian Stan has a 9 picture contract, that means he HAS to be in 9 movies, right? It really isn't that simple people. Stan's contract just means that IF Marvel wants his character back in future films, he is obligated by his contract to do those future films. But, by no standard does that mean that Sebastian Stan is DEFINITELY coming back as Winter Soldier/Bucky Barnes. He could, but he might not. Every actor that signs with Marvel Studios signs a contract like this because Robert Downey Jr.'s contract ran out and he had so much leverage on Marvel to get so much money because he IS Iron Man. Marvel won't make that mistake again. Hell, freaking Ty Simpkins, who played Harley in Iron Man 3, signed a 3 picture deal with Marvel. Will he come back? Maybe. If Marvel wants him to come back, he has to, but he isn't DEFINITELY coming back just because he has 2 more pictures on his deal. Basically, Sebastian Stan CAN return as Bucky but only if Marvel wants him to. NOTHING IS DEFINITE.
3) ONE SMALL QUOTE If you don't think Marvel Studios knows what they are doing, then you are an idiot. One reason people are hating on The Amazing Spider-Man 2 is because they feel like they know TOO much about it, with all these clips and trailers. The only fact we have in believing that Bucky could become Captain America is Sebastian Stan saying, "Yes[...] I think I actually have nine." referring to his picture contract. Marvel knows what they are doing and we don't. We the fans, are great at speculating and deciphering every little bit of information that we see. Bucky COULD become Captain America but until we get some real information to support this claim, then I will believe it. One small quote makes us think we are so smart but the real smart people are the people at Marvel Studios.
Just remember people, don't get too hasty. Cap 2 hasn't even come out yet and we are already speculating Cap 3 and beyond. We all just have to wait and see. Let's not get too far ahead of ourselves.