alt Hacker NewsI have a BA in Music Theory, I think maybe you should consider again. First off, Jazz relies on the same fundamentals and extends them, everything from Classical music is somewhat relevant in Jazz. So if it's only Jazz theory exclusive to classical, it'd be an advanced book indeed.
Second, it literally has a chapter on Popular Music and another on Jazz Theory, and "Classical" is not found in its chapter titles. So I don't think your critique is accurate.
Third, history and time matter. "Theory" came first in "classical" contexts, with codified rules pre-dating even Bach. Jazz was a much later invention that built upon these and other traditions. Both of the Jazz theory books I used in my BA in Music Theoryhad many elementary topics already covered in Classical contexts.
Yes, I think people have this fantasy that Jazz has anything new to offer in terms of music theory. That's false, everything used in Jazz was already part of the practice of classical music sometimes centuries ago. For example, improvisation was common in Mozart time and extended chords were common already in the 19th century. The only difference may be the terminology used in Jazz circles, but this is something that can be learned later if you want to specialize in that style.