Yeah, one time I was watching American Idol and there was this 16 year old girl who I thought was hot, I vocalized it and my sister gives me the biggest wtf face, until I super confused replied "... I'm 16".
It's super weird. Like every person that ever says anything to an underage girl is some creepy mustached 40 year old guy preparing the van.
I understand the instinct and it's good for mods to keep things in line (which they do) to prevent creeping on this girl. But I do think it can go a little overboard. It's a bodybuilding sub and she is posting her physique... of course people are gonna comment on it. Either disallow them posting altogether or just stop reading the worst intent out of benign comments complimenting her.