The reason for Jazz fans being upset at the Nuggets this particular season has been explained many, many times already on this board. Other than the Nuggets gaming the system and screwing the Jazz this year in terms of playoff positioning, Jazz fans don't care at all about the Nuggets. Nobody in any other NBA cities cares about the Nuggets.

There might be one or two other franchises in the league who are less relevant on a national level than the Nuggets have been over the past 2 or 3 decades, but I can't think of a single one right now.