The Marvel Cinematic Universe's Infinity Saga was a culmination of over a decade of storytelling, which made the stakes of the situation pretty intense. That meant that both Avengers: Infinity War and Avengers: Endgame were races against time. Where the former was a battle that was ultimately lost, the latter wasn't, and it allowed for those with unfinished business to finally deal with their problems and enemies. In the case of Steve Rogers, he got to live the life he always wanted, while Thor regained his confidence and rediscovered the hero he could be.
Source：https://www.cbr.com/bucky-barnes-never-reconcile-tony-stark/
