I gave it a listen the day it dropped. Initial impression is that it’s yet another masterpiece and they have neither slowed nor stagnated, but I really need to relisten to their full discography to contextualize it and give it a proper comparison/ranking.
Jellyfin doesn’t need any particular setup to work directly from LAN because it doesn’t ever try to use a central login provider the way Plex does.
The only reason OP is struggling with it is because they set it up so that they can only connect to it via Tailscale.