Which is something I've always wondered! How does the Lofi Girl channel on Youtube always have so much new music from artists I have never heard from?
The answer is surprising: real people and real instruments! (At least at the time of writing). Third-party stock music ("muzak") companies hiring underemployed jazz musicians to crank out a few dozen derivative songs every day to hack the algorithm.
> “Honestly, for most of this stuff, I just write out charts while lying on my back on the couch,” he explained. “And then once we have a critical mass, they organize a session and we play them. And it’s usually just like, one take, one take, one take, one take. You knock out like fifteen in an hour or two.” With the jazz musician’s particular group, the session typically includes a pianist, a bassist, and a drummer. An engineer from the studio will be there, and usually someone from the PFC partner company will come along, too—acting as a producer, giving light feedback, at times inching the musicians in a more playlist-friendly direction.”
I think there's an easy and obvious thing we can do - stop listening to playlists! Seek out named jazz artists. Listen to your local jazz station. Go to jazz shows.