Sheesh, I don't think there is any guitarist under the age of the late teens that has amazing phrasing.
Real emotion (and the phrasing it brings with it) will come as the kid has more life experiences and more to draw from emotionally.
Give the kid some time. He already has the technique down, something guys 4 times his age doesn't, and most guys 4 times his age have even inferior phrasing to this, so once he develops his phrasing by the time he hits his 20s, he will be a fucking king.
I'm sure Joe Satriani probably never had great phrasing a few years into his playing when he was 16-17 and of course we could see by the time he started making albums when he was about 30, he had the emotion of life experiences to back him.
I know I certainly didn't really begin to understand good phrasing until not so long ago, now that I'm in my early 20s.
As for the rehearsed comment, well, most jazz just isn't as "off the cuff" as you'd expect. It's not like a jazz soloists walks into a session not knowing the chord progression and not having any understanding of how to play around that chord progression, so a jazz soloist (unless he's playing some wild avant garde and free jazz stuff I guess
) is always going to have some amount of pre-learned licks they bring in with them.