The writing was already on the wall for a while: from this fall onwards, the age of iTunes is over, and music management in the Apple ecosystem will from now on be done in the brand new Music app, that introduces a new package format called “.musiclibrary” (containing the library database, etc).
And this will surely mean for Plex, goodbye to the trusty old iTunes plugin, hopefully to be replaced with support for this new library format.
I’m requesting that Plex devs use this opportunity to add an option to keep the Plex Music library automatically updated with changes in this Apple Music library, including playlists, smart playlists, search, and that we can not just stream, but also sync out of this library.