To compare with what bothered me, he would need to say, "As a Muslim, I feel uncomfortable going to x in America." There's a big difference between saying you feel uncomfortable with the clothes and saying you feel uncomfortable in a place based on your nationality.
I was referring to relations in general and these kind of remarks in general. No one remark is going to affect how people view Americans, but there is a stereotype of the Ugly, Arrogant American and comments like his are another drop in that bucket. So no, not life-altering, but I don't root for people who I feel are embarrassing in that way, especially since they signed up for a race around the world and should know they're going to experience a variety of cultures, religions, etc.