That's Some Technique

There aren't a lot of actors who could make this scene work as well as Natalie Portman. Most would barely be able to keep a through-line. Many would manage the proper expression and mimic the expected inflection of voice competently, but little else. Some would simply falter.

You forget Chris Hemsworth's windblown costume, superhero posture, and that hammer, and this becomes a scene between two people who care for each other. This should be shtick, however it resonates, thanks to Portman.