Looks Like Avengers: Endgame Has A Nod To Iron Man And The First Avengers
The short shots of their eyes can also be representative of the two Marvel heroes as characters. For example, when Iron Man goes into space, he reacts to it with closing his eyes during the moment, while Cap keeps his eyes wide open. And since Tony Stark has always had more of a bleak approach to the unknown, it’s great symbolism.
Article source: https://www.cinemablend.com/news/2491397/looks-like-avengers-endgame-has-a-nod-to-iron-man-and-the-first-avengers