I actually built a very crude python app that could generate basic melodies with MIDI. It can serve as a fun starting point if you want to remix common songs. But it wasn't a very fun project to set up. It's like this technology is out there but nobody really wants to develop it.

If I had to guess there are already a handful of fake record labels generating at tons of AI slop to just post on Spotify. Even if each song only gets something like two or three views over time they can still generate a modest amount of revenue. Oh wait Spotify has been caught doing that themselves