Not exactly self-hosted but I know many jellyfinners here would cherish this as well.
KDE's Android TV alternative, Plasma Bigscreen, rises from the dead with a better UI
www.neowin.netAnother KDE project, Plasma Bigscreen, is back from the dead with a much better UI spread across the entire shell.
It’s an alternative shell for Plasma, so theoretically you should be able to do anything in it that you can do in Plasma.
On my Arch box it installed a minimal set of Plasma utilities to support it, which means my setup is still very limited (and I can’t turn off screen lock!), but I haven’t tried if it would change if offered a full Plasma install.
I can most certainly launch Steam, Kodi, Jellyfin etc.