I wouldn't worry about it too much. Every girl goes through that, they're called your formative years for a reason. The start of HS is basically a reset where you go from chasing whatever fancy catches your attention shamelessly-ish to consciously developing an identity filtered through the social pressures of wanting to fit in. It starts to wane around 17 when we start feeling confident enough to be ourselves, but on purpose this time around. She'll be fine.
I like how people respond as if I haven't gone through high school, or am aware of the typical changes that are associated with that period, in boys and girls. I'm also not saying she's not going to be fine. I'm just shocked at the impact of social media on their experiences and have concluded that it's impossible to resist.
They'll all fall in the bell curve so of course they'll be alright, but they'll be alright in a way different world than the one in which we were alright.