> I can specify the whole OS including the packages I need and the configuration in one declarative setup. That one place aspect matters to me more than it might sound at first.

It took me less than a day of experimenting with it to learn that it is one place only in theory.

The second you start googling „how do I install xyz“ you discover there are also flakes. And others have some sort of convoluted git like method. And there is a package manager thing. And the direct config file editing like in this article. And a disposable temp install of some sort. And naturally software guides don’t give you instructions for all - they’re opinionated.

Felt a lot like being on Debian and the software only comes in .rpm

That really took the wind out of my sails because like OP I liked the basic config file part