I’ve noticed that plex fails to read embedded metadata in matroska files despite reading embedded metadata in mp4 files.
This feels like a regression to me and - if it isn’t - bringing these parsers to feature parity makes sense, especially now that more and more people are using codecs like VP9 that cannot go in mp4 files.
In addition:
There’s an existing feature suggestion to read metadata from other containers.
I suggest you vote/comment in that thread instead having a duplicate that’ll only distract/disperse votes and attention (hence we strongly encourage to search before posting duplicate suggestions).