I've used NixOS, it's a great project and has some benefits that can't be overstated, however if you're going to give it a try completely you kind of have to go down the rabbit hole. You will basically be learning a programming language that will let you configure your system. It took quite a bit of getting used to to understand how the language nix works, as it wasn't familiar to something I had used before. One might not have as much difficulty getting used to it as I did if they are experienced with functional programming, which I've only dipped my hands into before.
I'd recommend giving it a try if you have some time on your hands to get used to it, but you shouldn't be expecting a quick switch.
I disagree. While to be a power user you might have to learn all the syntax of the OS, I have been using NixOS for a couple of years, and have my configuration set up by borrowing other configs from the Web.
Additionally I'm a heavy Emacs user, and couldn't type a single line of elisp. I get that I'd be better in Emacs if I knew elsip, but that doesn't stop me configuring my text editor by borrowing code from others.
I'd recommend giving it a try if you have some time on your hands to get used to it, but you shouldn't be expecting a quick switch.