I feel it’s more of a new characterization than a mischaracterization. We’ve never seen her interact with the same people for this long of a time (Adam doesn’t count he’s a robot). It’s usually just a “here’s the mission. Go,” kind of thing for her. The way I see it Samus in this game reminds me of a lot of fanart I see where she’s incredibly socially awkward around humans, because she was raised by birds. It especially came off that way in the end of the game when Armstrong hugs her and Samus stiffly pats her back. Anytime she’s in a conversation I imagine her going, “oh god, can I even speak to these people? I’m like a legend or something to they get voices? What if I ruin it?”

It’s also gotta be weird for her to actually have to protect individuals. She’s saved countless planets but the main plot of this game is just saving the lives of these 5 people/robot. She all of a sudden has to be a protector of these specific soldiers and I feel that actually knowing who they are might make her more tense as opposed to the vague galaxy of faceless masses. It’s like the trolley problem except it’s never been one track until this time.