I can see that being the case with a black person, but from what I've seen there are quite a few reservations in that part of the US so perhaps a Native American wouldn't stand out so much except for the height she mentioned. 6' 5" would stand out anywhere except in a basketball team.
Just for general interest, I drove through a Blackfoot reserve in Alberta near the Montana border and the young men are exceptionally tall, they all look like basketball players, and that was confirmed by a well-over 6 foot guide who said it's because they now grow up with good nutrition.