Disappearing Jazz?

I suggest you take a look at the Downbeat Magazine Reader's Poll and Critic's Poll to discover today's artists. There is no shortage!

SO MUCH JAZZ , now and then!  LEE MORGAN  is amazing!  Nicholas Payton is Fantastic! Only two of so so many!

I have several modern Analogue Productions vinyl re-issues of classic jazz LPs. They are uniformly superb. 
My perception is that classic jazz LPs are often reissued, often by reputable labels that produce superb masterings, thusly providing fans with an easy, legitimate alternative to purchasing uber-expensive original pressings.
Kamasi Washington’s album from a few years back was very acclaimed and, relatively speaking, quite popular as far as jazz music is concerned.  It’s called “jazz” for a reason. It ain’t “pop.”

It’s cool that this new Todd Field film, Tár, has inspired interest in classical music among the masses (particularly Mahler).

I don’t personally perceive jazz and classical music to be in a state of endangerment any more than they’ve always been “an endangered species.”

Considering how peripheral and marginalized these types of music have been for decades, one could argue the accessibility to all music via modern technology has made jazz and classical more accessible than they’ve been in a long time.

Jazz, as most people think of it, flourished in particular during the 1960s-1980s which was a period of radical individual self expression and spiritual enlightenment. (An era in history known as "The Consciousness Revolution"). It was a period of breaking away from the institutionalized, conformist STEM era of the 1930s-1950s. Incidentally, the 1930s-1950s was the period Muzak was created, whose goal was to standardize all genres into inoffensive background music for worker productivity. (Hm, ring a bell these days?) If you listen to a lot of artists like Miles Davis or Bill Evans, their work changed radically by the late 60s. Jazz can exist in any period, but most of the emotionally charged and groundbreaking work was done in this period.

We’re back to the period of conformism, group participation and standardization with negative connotations attached to individualism and subjective self-expression, so art and culture is struggling. It’s not just you, everyone I know in the creative fields has noticed it. There are some artists who continue to push the limits or play with real soul, but they’re mostly underground.

 You can find more outside Jazz than ever. It's never been popular, but as you mentioned, who cares.