Tyson isn’t afraid of teenagers.
He distrusts everyone equally, regardless of age, but Tyson is overly aware of how easily teenagers are manipulated by people like him for the web or other causes. Despite his best of intentions, Tyson knows that he is one of the worst influences to be around a teenager.
When recruiting for the web, Tyson goes out of his way to avoid anyone too young, no matter how much talent they possess and - if he suspects that others have their eyes on that person - will try to direct them elsewhere. If they are still as useful to the web once they’re older, then it’s no longer Tyson’s responsibility.