Jazz is still very much alive!
Just because you don't hear it on the radio doesn't mean it's not alive!
Students can attend even Berklee (and I'm sure other colleges) for
Jazz Composition!
IMO, Jazz is still very much alive, and will never die. It will just evolve, just like any other musical genre. It's not as mainstream today as it was in the 50's, but it is still enjoyed by many.