I just wanted to comment about the smiling factor.
My one and only up close to an international meet opportunity was volunteering at the Senior Pan Am Qualifications in 2014. I was "security" so right freaking there beside the beam, supervising the warm up areas, the corrals, etc. it was so awesome! My dd even got to Marshall and loved it too!
Anyway, my point being that i was there with these girls behind the scenes. It was no smile and giggle fest, trust me. Even as teams sat together, even as the American team was clearly so far ahead of almost everyone on most events, these girls were concentrating, focused and serious.
It wasn't broadcast, as far as i can remember (but can be corrected if I'm wrong), but i think in the major competitions where they know they are constantly being followed by cameras and media, they put on somewhat of an act.
I can also say, my dd loves gymnastics with all her heart. She loves the challenge, the training, the accomplishments. But competing makes her very nervous. She does not smile out there. But i will tell you that in her own way she is enjoying the efforts of her hard work.
Just another perspective that just because they aren't smiling doesnt mean they don't want to be there. Oh but my dd does have the "salute smile" out of respect for the judges at the start and at the end of her routines, no matter how the routine went.