I understand that (and as a coach had to deal with the "presentation" aspect re: choices of game uniforms, regulation of practice apparel, pregame attire, etc. for girls' volleyball, basketball, and softball teams). I saw coaches allowing their female middle school (basketball) athletes to practice in sports bras and raised objections to that as being inappropriate. I have been a vocal critic of over-revealing and uncomfortable attire for female athletes that were not matched by their male counterparts and seemed to serve no athletic purpose...and applauded and have been encouraged by recent female athletes and teams who have defied requirements that they wear skimpy attire in competition.
So, speaking as someone who had to enforce teenage dress codes and someone old enough to be this young lady's great-grandfather, let's address the elephant in the room. The problem of sexualization of minor females in media and advertising is not new (and now we can add the explosion of exploitation on the internet and social media). And the particular focus given to females athletes' appearance contrasted with the focus on male athletes' sports performance still goes on (although even male earning power can be enhanced by looks that the masses find appealing). As someone else pointed out, it's naive not to think that sports agents and companies won't capitalize on their clients' looks, and many athletes will not only go along with this approach because it's financially lucrative but because it's personally flattering.
The comments by others made were, in my view, simply factual observations. The picture was a "glamour" shot. It did indeed look like an older model at first glance, and not like a high school athlete . It is the type of look that gathers a big social media following (Hailey Van Lith didn't have a huge amount of followers simply due to her basketball skills). No one made comments about the girl's body or made suggestive remarks as far as I could tell. I would say my attempt at a joke about her uniform being too small would come closest, and in hindsight, I can see that someone might find that to be offensive. I've commented in the past about how silly I find the "rolled-up" shorts look to be, essentially appearing like a diaper to my eyes (and I've been told that it's the athletes' business how they wear their shorts, so I know opinions vary). At any rate, the critique of the uniform seems to get lumped in with the person.
So, having been one of the offending parties, I'll address the elephant. The picture in question, IMO, was a poor choice to accompany the announcement of the accomplishment. The athlete pictured has a wide number of pictures available, from game shots to the familiar studio poses with basketballs, aggressive stances, etc. that we typically see. The picture chosen is vastly different from the majority of her "basketball" photos which seem to emphasize or at least include the sports angle over the personal appearance angle. The contrasting approaches are night and day, and it seems disingenuous to purposely choose a photo emphasizing physical appearance and then expect people to ignore the presentation...especially since the presentation seems to be exactly the reason the photo was chosen. It has everything in common with the athlete's non-sports, "social" pics as opposed to her "sports" pics (even the posed ones). In other words, any "sexualizing" of the minor comes from the photo itself.
But the lesson seems to be not to comment, good or bad, about the appearance or presentation, even tangentially, of any minor athlete. I would note that no specific or even general comments about the athlete were made other than the observation that she looked like a "model" in the pic. Given that there are many minors who are professional models and that athletes do themselves sometimes appear as professional fashion models, it seems not only to be an innocuous observation but one with which most would agree without finding it the least bit "creepy."
Anyway, just a perspective. I'd wager that most of us will never again comment about either uniforms or appearances in this forum, even for college athletes.