I’ve been running this on a Raspberry Pi 3b for a couple of years now — it was easier to install than Plex, doesn’t try to upsell me to a subscription when I listen to my own locally-hosted library, and runs fine over the LAN. The Jellyfin desktop apps work pretty well on Mac, Windows and Linux.
I only use it for audio, not video, so I don’t know if the Pi 3b and its relatively slow processor and network throughput would be enough to handle video. I reviewed it on my website a while back in case anyone’s interested: https://hyperborea.org/reviews/software/jellyfin/