Assuming he'd have no problem getting girls because he's young is not considering a lot of other factors that play a vital role when it comes to mate selection. It's like saying I must have like seven boyfriends simultaneously because I'm doing fine as an escort, but then it turns out I've never had a boyfriend. *Gasp* You never know what hidden disabilities people may have that require more effort than a blanket advice like "just download tinder" or "just go out more", "just be more confident", "just talk to her", sometimes it's better to make use of the 70% great skills you have instead of letting your life be ruined by the 30% crap patiently vegetating and growing old in silence because you're waiting for that special person who accepts your 100%. I think it's pretty cool that he's working on his problem and chooses to learn from professionals instead of potentially getting traumatized by the harsh world of dating where it's true that he can learn things he cannot learn elsewhere, but I think everyone deserves an easy start, and it's totally their business whether they want to keep playing life on easy setting til eternity, or graduate at some point. Just because y'all thrice his age, may not necessarily mean you know what's best for him, I don't either, I just know how much it means to have good mentors when you have insecurities.
Don't wait to get confident. Just do it, and eventually the confidence will follow