I like setting up my SteamDeck docked on my big TV. Newer games look rough at 720p, but playing older/indies at 1920x1080 + 4 controllers is a great experience.
Let’s say I want the option to boot into a frontend that makes it easy browsing a local collection of shows/movies on a USB. What are my options? So far Kodi seems to do exactly that, but I’ve heard of Jellyfin/etc.
If you want a use-case like that, Kodi is probably your best option.
If you wanted to host your media on a different PC and use that as a server and then stream it to your Steam Deck, then Jellyfin would be the go-to choice.