Similarly while docker's CLI interface is relatively nice, it's even nicer to just take my phone, open a browser, and push "update" or "restart" in a little gui to quickly get things back up & going. Or to add new services. Or whatever else I want. Sure I could SSH in from my phone, but that's awful. I could go get a laptop whenever I need to do something, but if Jellyfin or Plex or whatever is cranky and I'm already sitting on the couch, I don't want to have to get up and go find a laptop. I want to just hit "restart service" without moving.
And that's the point of things like TrueNAS or Unraid or whatever. It makes things nicer to use from more interfaces in more places.