- Peggy’s narrative in the Captain America franchise is about Steve.
- Bucky’s narrative in the Captain America franchise is about Steve.
- Sam’s narrative in the Captain America franchise is about Steve.
- Natasha’s narrative in the Captain America franchise is about Steve.
They are his movies. Everything is his POV. You learn things, in order to help connect with the audience, but ultimately, they are about him. Everyone else has a supporting role, to aid his story, whatever it may be.
Bucky/Sam eventually take up Captain America title, whether we will see that in MCU remains to be seen. If that does happen the POV will change to them, making the stories about them, everyone revolving around their narrative. (granted I don’t hear much from sam/bucky people. they seem to be genuinely happy their character exists)
Natasha has been royally screwed and deserves her own POV, so you can actually keep complaining about her. For four movies we know minimal things and that’s crap.
Peggy has Agent Carter, where it’s her POV. It’s her story. It’s her life. There, Steve became supporting to her, and that’s how it should be. Because it’s about her. Captain America is about Steve. Agent Carter is about Peggy. So, no, Peggy does not deserve better in the Captain America franchise because they are not about her. They were never about her. They will never be about her. She is there solely to aid in Steve’s story, to get him to where the Russo brothers need him to be by the end of Cap 3.