On Infinity War:
The character you love isn't gone even if their role ends. First off, it's Marvel and everyone comes back. But what brought you to adore that character is still alive and thriving - their strengths and wisdom still follow you.
This is goodbye, but it's not the end.
The Captain is a symbol. While Chris Evans is a superior individual for the role, it doesn't mean he is required to be the Captain forever. He's a person, but Captain is a character, one who can survive well into the future.
PS - Weeks ago, I had an idea to put a purple Captain image here, but the posters took care of that for me. Synced.
PPS - two Captain posts in a row? Am I burying everything else in my life to make room for this movie? Nah, but more details will come.