Plex can only import smart playlists if the playlist can be recreated in Plex itself. Some playlists can’t be recreated in Plex. Can you provide the specific rule in iTunes for that?
Ok, interesting. Then I can understand many of my smart playlists will not translate. For example, this one is tracks added on 25 July 2016. Similarly, my playlist of Loved tracks will not work.
However, playlists based on an artists or albums should work.
For example, I have a smart playlist for artist contains cibo matto
In plex, I can see I have 8 albums under the artist Cibo Matto.
This is from the log:
Plex Media Server.3.log:Nov 08, 2021 08:07:15.721 [0x7f4c38a38b38] DEBUG - iTunes importer: playlist 'cibo matto' (smart: 1)
Plex Media Server.3.log:Nov 08, 2021 08:07:15.722 [0x7f4c38a38b38] DEBUG - Added new metadata item (cibo matto) with ID 1405018
Plex Media Server.3.log-Nov 08, 2021 08:07:15.726 [0x7f4c38a38b38] WARN - iTunes importer: unable to parse the smart playlist.
Plex Media Server.3.log:Nov 08, 2021 08:07:15.726 [0x7f4c38a38b38] ERROR - iTunes importer: Couldn't import playlist cibo matto, deleting.
Plex Media Server.3.log:Nov 08, 2021 08:07:15.726 [0x7f4c38a38b38] DEBUG - Destroying metadata item 1405018 (cibo matto)