Chael Sonnen and Phil Davis didn't see a drop in popularity when they beat Stann.
Stann is a stand-up guy and a war hero. He has the respect of most Americans, but I don't think that we really dislike people who beat him. Both Stann and Wand are honorable men who give it all in the octagon. We don't want Wand to throw the fight, we want Wand to try his best to win, and if he does, good for him.
Stann also isn't the legend that Wand is. I don't know any MMA fan who dislikes Wand.
Of course, I don't speak for all Americans, but this is my take.