"Some are called "16 year olds.""
True enough, but they aren't really doing searches for the 15 year olds. They're all around them. Most of the 16-year-old boys I know search for somewhat older women on the internet. Not too many 15 year old girls on the porn sites, I'd guess.
Obviously, I'm not talking about teenagers and their relationships.
I agree. Mostly FBI dudes posing as 15 year old girls (though I don't know how they handle the 5 o'clock shadows in the pictures).