One of the biggest difference between movies and comics is that actors get older and some of them are going to want to move on from the role. Not everyone wants to do the same job forever and they're not obligated to keep playing the same character. They can't regenerate like the Doctor and people aren't going to except a James Bond situation at this point. Luckily Marvel has hundreds of characters and plenty of the heroes titles have been taken by other characters.
Evans was done. Captain America had to have some conclusion to his story the problem wasn't that he left though. The problem was that Steve abandoned all his friends to hook up with a woman who already moved on and I guess Steve just let all the bad things in history happen. Not the ending people wanted.
It's exactly that. I don't think anyone expected Chris to stay in the role forever although I wouldn't have minded it because he's the perfect Steve Rogers but he should have been given a send-off that made sense for his character. The problem is the Russos didn't quite understand the core of Steve's character so when they or the writers claim they wanted him to "rest" it doesn't make any sense.
Fighting for what's right, defending the little guy, rising up when someone hurts those who can't help themselves, standing up against oppression and discrimination... all this isn't something Steve did, it's who he is! That's why he's so good at it and why he inspires everyone that gets to know him. Steve is the damn personification of freedom.
He can't rest because as he said himself in CW:
If they wanted him to retire from being Cap, that's awesome. In fact it would have followed what he had expressed in TWS, that he was thinking of retiring and doing something else because all those things (defending the oppressed, standing up to discrimination, etc) they can be done while wearing the suit and carrying the shield... or not. There are a million things Steve could have done after passing the mantle on to Sam.
And let's not kid ourselves, all these fans saying that if Steve had stayed in the present then Marvel would be forced to explain his absence whenever something big happened... when have they known Marvel to explain plot holes? Don't make me laugh! 😂😂 As it stands right now after EG we have no clue what happened to Steve: is he alive? is he dead? is he on the 616 timeline or did he go back again? is he on the moon? We don't know!
Steve could have retired, Chris would have said goodbye to the character and the others could mention his name every now and then like "I met with him last Sunday, he was designing costumes for the Pride march" and no one would have an issue with it. The cynical part of me however is convinced that they got rid of him because who they truly wanted was Captain Carter, a character much better aligned with their ideas who's far easier to handle.