I still am a fan of jazz, but I agree with the sentiment. By the late 1960's or so, jazz innovation was beginning to wane in favor of copying elements of rock music, seemingly in an attempt to gain more listeners.
Some great jazz/rock fusion came out of this (e.g., Weather Report), but it was more or less an evolutionary dead end for jazz. By the 1980's, jazz started going back to the styles developed in the 1950s/1960s, and most of the jazz we hear made today is just rehashing what the masters did during that era, only not as well, and without the creative freshness.
I personally think pretty much every genre of music has hit up against this lack of creativity recently, though... I really don't hear much new music that I think is all that great.