Jellyfin is awesome, but there's a few caveats for me. - Android TV app is quite unstable. Even if you make it do direct streaming, it's not a flawless playback - Sometimes hangs when clicking next episode. I also kind of wish the login experience was a bit better. - Android App is decent, but for music it's unusable. I'm still using plex + plexamp because that experience is just so much better for me.
But, I don't regret moving my videos to JF. Plex Android app had terrible QA/QC where it would have regressions consistently every month. A bug where rewinding 30 seconds would push you forward instead of backwards would return at least 1 update every 2 months and that was frustrating.