Hyperbole means exaggerating something, usually for emphasis or humor. Even taking your comment as hyperbole, the intended, non-exaggerated meaning still appear

Hyperbole means exaggerating something, usually for emphasis or humor. Even taking your comment as hyperbole, the intended, non-exaggerated meaning still appears to be "this person has insufficient experience to speak on this subject." But the person in question is actually very experienced in this area. Given that, I don't think we can blame James if he didn't understand — it's hard to see what the actual meaning behind the statement could have been.