I’ve never had any issues with jellyfin. Maybe your use case is outside of what it’s for, but for watching series and movies it worked with everything I could throw at it for me.
you've most likely never tried to view subtitles. It's well known that its subtitle support isn't so good (to put it lightly). It seems to be unable to stream subtitles out of an MKV itself and has to extract them and send them separately. (or at least thats what it seems like from observation).
But if you use ASS subtitles, which are entirely unspecified and unsupported and only have a single working implementation that requires half of Wine to work correctly, well, then you're fucked.
I use subtitles all the time and they work really well for me - both embedded and separate files. I'm streaming from an SSD though, maybe that makes a difference?
Somehow my Jellyfin Android TV app became incompatible with the server application on my home PC and I can no longer watch videos, so had to head back to Plex or Kodi+NFS mounts.
