But it would not work on older non-GNU versions of tar.

GNU introduced the “–foo” style long options, and it was a long time before Unix versions began adopting them.

Tell me you’re bi without telling me you’re bi

Sudo not even needed unless you were running vim as root

For a privacy friendly OS, surprised nobody has mentioned Freedombox

It’s designed explicitly for your use case, along with an easy path to other self hosted services. When you’re ready for more than it offers through the web interface, it’s a full Debian install under the hood - so you can install whatever you need to. Privacy friendly and super stable, with smooth upgrades to new releases and security updates for old versions several years after the new one is available.

As far as hardware, your old computer is probably more powerful than a Pi and can support more drives, but the Pi will be more power efficient. As others have mentioned, if you care about your data long term then backups are a must, so a separate NAS or a Pi with a large drive for backup storage is a good idea as well, whatever OS you choose.

It’s the only one that’s actually UNIX.

Uh, no. I mean, yes it’s actually Unix, but so is BSD. In fact, OSX is only Unix BECAUSE BSD is - Darwin is BSD derived

Not true. Free cellular connections exist in some places. And there are non-cellular solutions like LoRA trackers.

There’s more truth to that than most people realize: Linux is only one kernel option in Debian:

Debian GNU/kFreeBSD

Debian GNU/NetBSD

Debian GNU/Hurd