>>724586024
it's a made-up genre
it doesn't exist
no website lists post-avantjazzcore as a real thing
It was some meme /mu/ made up in the late 2000s to make fun of hyperspecific genre names

But then it turns out there's a bunch of stuff that could be considered "post-avant jazzcore" which makes it even funnier.
https://www.youtube.com/watch?v=dSWb9mNn9J4