I am looking to build a machine to use for file backups and some light media serving (PhotoPrism, Calibre, and the like). My plan is to take a retired desktop, throw in every old drive I have lying around, and merge them with Greyhole.

I am a seasoned Linux user (in containers or on machines being managed by others). I am comfortable with CLI basics and should be able to use the system entirely over SSH and web UIs, so I am fine without a window manager. What I am not fine with is system administration (and do not want to spend time fixing issues that constantly pop-up).

Ideally, I would want to find a distro that I can install by accepting reasonable defaults, configure my storage and my various applications, create a cron job to periodically update packages and reboot the machine, and the machine will just keep working with no intervention on my part. I realize that that is an impossible goal, but I want to get as close as I can.