You rock! The Jellyfin Android TV app on a LineageOS-Pi4 is my current preferred way of bringing Jellyfin to my TV. I tried messing around with Kodi-based solutions for a while but if you don’t like the default behaviors there then it’s an absolute nightmare timesink to reconfigure. AndroidTV Jellyfin client - install, open, everything is in its place already.

Then I installed Kodi, along with the Kodi Jellyfin add on. The add on syncs the Jellyfin database to the Kodi one, so you use the Kodi interface to browse the Jellyfin content. This seems to work great!

Which Kodi theme are you using? I haven’t really found a satisfying fire-and-forget solution that could deal with 6+ different kinds of libraries and also didn’t require me to manually set up every menu option over the course of 3 hours.
Have you found an elegant way to manage multiple different users?

The linked build is based on LineageOS, not stock Android. Should be fully FOSS.