@submana things I currently use SBCs for (some of these use cases won't run on a Pi Zero, but I'll list em all :p)
PiHole
Plex
Plex TV clients
MPD server
Baby monitor
Gogs git server
Shiny R server
Home Assistant
Nextcloud (although that runs on an HP microserver right now)
I *may* have too many SBCs ... :)