Linux, niche?! Idk where you’ve been, but Linux is ubiquitous and runs everywhere.

It’s about scale mainly.

A nixos host can be viewed as a solid state environment, in some respects. At least from a systems management perspective.

If you scale up to more than one host, that you want to keep in a completely manged state, nothing really beats a model like nixos (or guix, although I lack experience).

Having the complete system state of n machines, where n > 1 nixos is hard to beat. I have extensive experience with tools such as ansible and salt, but the state management of nix is just unbeatable. It’s, IMO, “how it’s supposed to work”.

And with nixos you usually don’t have to nuke anything - a new system generation is enough.