Earlier quoted context omitted.
Dance music is alive and well, it just doesn't sound like jazz anymore. Being a type of music that emphasizes the here and now (that is, the dance floor), why should the music producers use production techniques and instruments of a bygone era? Also, if we're looking at the big picture of "the story of american music", disco very much comes from the same lineage as jazz.
Please don't tell this to the 150+ people who came out to the (Swing) dance I threw with the Dixieland Express. Nor to the scores of dancers that will be attending the Hot Jazz Jubilee in a few weeks. The downfall of jazz as a genre for dancing began with an arbitrary dance tax. It continued with the era of "The Twist", which encouraged people to dance by themselves, and continued on into the disco era, which did mor…
However, most post-WWII jazz was not composed for danceability, and much of it is not very danceable (Try dancing to "Giant Steps" or "Brilliant Corners").