Chris Evans might have recently revealed his true feelings towards Captain America's costume, ranking it poorly among the Avengers' - but it's definitely not the worst. Being the first Avenger to appear chronologically, Captain America has donned many different outfits through the years. While some were truer to the comics' versions than others, Captain America's costumes managed to change quite a lot without losing the ability to be recognizable for what Rogers stood for as a character across the first three phases of the MCU.
Captain America's costume in Avengers: Endgame was only the final version of many revisions through the years. Captain America's first costume in Captain America: The First Avenger was used only to raise morale during World War II, but the same movie also introduced Cap's first serviceable costume, more toned down in its colors and era-appropriate in its style.
Captain America's Avengers costume blended both styles, with the colors' vibrance reminiscent of Cap's non-usable costume and Rogers' second costume's usability in combat. The subsequent appearances of Evans' Captain America in the MCU showed a costume that became even darker and more rugged in Captain America: The Winter Soldier and Captain America: Civil War, where Cap's costume's colors were more subdued than in the past, reaching peak darkness in Avengers: Infinity War, where Cap's costume's color changes were almost imperceptible.
Finally, Avengers: Age of Ultron's version of Captain America's costume was slightly brighter and bluer, and Avengers: Endgame had Captain America's costume regaining some of its flashier attributes both in color and style, especially in the way its armor highlighted the star at the center of Cap's chest. -Collider