You are assuming they aren't in a relationship or have an attraction because your default assumption is straight unless you see evidence to the contrary.Why is it not equally valid to assume the default is gay unless you see evidence to the contrary?However, there is absolutely nothing implied in the scene to merit that. A non-spoiler version of this would be the relationship of Steve Rogers and Bucky Barnes in the MCU.Taking the movie and scene as it is, saying "she's gay! Steve and Bucky are clearly very good friends who have gone to hell and back together.
Compare that to the Steve and Bucky relationship, or the Valkyrie scene: There's nothing that overt.Can't they just be, you know, extremely good friends and love each other because of that?I understand that there is a massive under representation of gay characters in pop culture, which needs to change, but claiming that a character is something that they aren't just because you have an imagination isn't the answer.A counter example would be a character in How to Train Your Dragon 2 named Gobber.Gobber was just a dude in Dragons 1, but in Dragons 2 he had a throwaway line of (paraphrasing) "You see, that's why I never got married. That is an ambiguous phrase, but it clearly had intentions.Why shouldn't audience members read gayness into a character? They never actually say they aren't gay or they are only friends.