Linux

Or that code is not cleaned up

Knowing codebases, literally always it is simply messy code they dont want judged

I used to run their closed cli client years ago, but only when connecting to grab wireguard configs, then I closed it and connected with that config without it, which worked well*.

I also remember strace showing it reading a bunch of stuff including /etc/os-release. So they at least knew what distro you were using 😉

It was okay for me because I knew how to deal with it, although I'm with a provider that provides configs directly so you don't need to use any service-specific clients.

Nord was never, or should have never been, a "privacy" choice, unless you are the kind of person that falls for paid reviewers and comparison sites, or marketing bullshit like all the X eyes talk.

*you can do that with any client that connects through wireguard since you can run wg showconf on the connected wireguard device. Although you would have to do some scripting yourself to replicate other steps like DNS and routing. I don't think I was the only one doing this.

Not necessarily. Could just mean they use code that is not theirs and their licence does not allow publishing. Happens more often than one would think.

So that they can make a better user experience, customized to their brand, and in turn be able to cast the widest possible "customer net". They could also be using custom openVPN software so they can do more advanced protection layers, tailored to their service ofc

OP already answered, but it boils down to user friendliness for beginners.

All VPN providers I used also allow you to download a .opvn file if you just want to start a client with the config file from the CLI, but for non-techies it's a no-go.