I can't see any reason they couldn't go together. Fully using nix is a trip off the deep end of the learning curve, but there's nothing preventing a beginner using a predefined nixos configuration so long as they stay inside the guiderails. With a bit of care, it should even be possible to let them enable whole add-in .nix files to do things like "check this box to enable proprietary nvidia drivers" (which includes a predefined module that handles that).