Worst ending? Avengers: Endgame.
Steve Rogers abandoning his team, his closest friends, and especially Bucky to return to a woman he knew for roughly two years during World War II never made sense to me. They barely had time to build a relationship, shared only one kiss, and after years living in the future, he was no longer the same man Peggy originally knew. How is that fair to her?
What makes it worse is everything he would have to ignore by choosing to remain in the past. He knows another version of himself is frozen in the Arctic. He knows Bucky is being tortured. Natasha and countless other girls are trapped in the Red Room. Howard and Maria Stark will be murdered. Tony will be kidnapped. Bruce will become the Hulk. Hydra is growing inside SHIELD. Future wars, attacks, and disasters will cost thousands of lives.
The Steve Rogers I know and admire would never quietly live alongside that suffering. His entire character is built around running toward danger, not away from it. He fights for the present, not the past. He does not abandon people who still need him.
Endgame asks the audience to believe that Steve suddenly stops acting like Steve Rogers, and that never felt emotionally truthful to me.
What made the ending even more frustrating was the way Steveās relationship with Peggy became retroactively treated as the singular emotional truth of his life.
And. The idea of Steve as an āeternal virginā never appealed to me. It feels less like a historically grounded interpretation and more like a modern romantic ideal projected backward onto a man raised in another era. I also dislike the implication that someoneās worth or moral purity is tied to chastity. Steveās character was never built on sexual innocence. It was built on empathy, courage, restraint, loyalty, and respect for others.
Historically, the idea also does not really fit the social reality of the period Steve came from. Men of that era were not universally āsaving themselvesā for marriage. What existed was a strong culture of discretion and a very unequal social divide between women considered suitable for marriage and women considered suitable only for casual encounters. Since the Golden Age comics, Steve was always portrayed as respectful toward women, chivalrous, but never naive about them.
Peggy gained importance gradually through reinterpretations and retcons. Originally and chronologically, she was part of Steveās wartime past, not the defining center of his entire emotional life. Sharon Carter was his most recurring romantic relationship, and over time Steve also had other relationships, affairs, and even a fiancĆ©e, Bernie Rosenthal. Rachel Leighton (Diamondback) was one of the few women he openly dated without hiding his identity as Captain America. Across eight decades of stories, Steve was consistently portrayed as emotionally capable of moving forward and forming new attachments.
The MCU gave Peggy much greater narrative importance, but even there Steveās characterization is more complicated than āa man frozen in time waiting for one woman.ā
In Avengers: Age of Ultron, Steve explicitly says: āThe guy who wanted all that went in the ice seventy-five years ago. I think someone else came out.ā
In The Winter Soldier Civil War, he kisses Sharon. (thanks @speromint )
The emotional constant throughout Steveās life was arguably Bucky, the one relationship he never truly let go of. Personally, I suspect Endgame redirected Steveās ending toward Peggy partly because Marvel became uncomfortable with how emotionally central that friendship had become in audience interpretation.
As for changing the past, I do not think comparisons to stories like Flash really apply. The moment Steve returned to the 1940s, the timeline was already altered by his presence alone. He had spent years living in a different century, shaped by experiences, wars, technology, and social changes that did not exist in 1945. He was no longer the same man who originally went into the ice.
That tension is explored directly in the comics Captain America: Man Out of Time, where Steve struggles with aspects of the past he can no longer accept, including segregation and other social norms of the era. Steve would never assassinate people or become some reckless timeline manipulator, but I also cannot imagine him quietly living through decades of injustice without speaking up or defending ordinary people.
Steve Rogers' entire character is built around moral action. Even if he never threw a punch, his influence, his voice, and his values would inevitably change the world around him.