One pivotal Iron Man and Captain America scene in Avengers: Endgame would've been better if the superheroes switched parts in one scene. The 2019 Joe and Anthony Russo film had a lot to accomplish in of narrative, couple that with the high expectation from that public and the work was cut out for Marvel Studios. All that being said, arguably its most important task was to wrap up Tony Stark and Steve Rogers' arcs, which they impressively did. There's just one moment in the film that would've been better had it played out a little differently.
Following their fall-out in Avengers: Infinity War.
While each of Tony and Steve's interactions in Endgame were memorable and sometimes even poignant considering their complicated history with each other, a significant scene between the two would've made better sense if the roles were reversed between them. After failing to secure the Tesseract during the Battle of New York leg of the time heist, they took a risk and jumped further back to the '70s but just before they did that, Iron Man asked Captain America if he trusted him, to which the Super Soldier said yes. The scene signaled that they're fully putting their conflict behind and focusing on the task at hand, but it's odd that Tony was the one to ask about Steve's trust when it was the latter who blatantly lied to him in Civil War.
The introduction of the Sokovia Accords may have kickstarted Iron Man and Captain America's conflict, but it's Steve's decision to intentionally hide how Howard and Maria Stark really died that broke them apart. Upon seeing the footage of a brainwashed Bucky, who was still operating at that time as HYDRA's operative known as the Winter Soldier, Tony asked his fellow Avenger if he knew about it. Instead of truthfully answering, Steve waffled; implying he knew the Starks were murdered but claiming he didn't know it was Bucky. When asked again, Captain America eventually itted, explaining he hid the truth because he wanted to protect Tony. This was a massive disappointment from Steve considering he's the most moral among the Avengers. What's worse for Tony, his father was always fond of the Super Soldier.
In hindsight, if Captain America had come clean about it much early on, he could've lessened the blow on Iron Man. Granted the genius billionaire would've more likely also be mad, it wouldn't have come at a very important juncture in the MCU. Zemo's carefully laid out plan was meant to catch Tony off guard, making his reaction more visceral and erratic. The fact that no one else was around didn't help the cause as there wasn't intervention from their allies.
Avengers: Endgame never really dwelled on the details of Iron Man and Captain America's personal conflict; it's even unknown if anyone else knew about it. But considering what really happened between them, the film could've found a way to establish that they're moving on from their fight without Tony having to ask Steve if he trusted him. Otherwise, they could've totally scrapped the dialog since their private get together before the time heist was more than enough to show that they're back on the same side to reverse Thanos' snap.
