@civodul There are multiple things to consider here: previous experience with lisps or haskell can sway one easily. Having programming experience too: imo Nix is easier to grasp, because its a more limited language. But if you're familiar with lisps, then Nix will suddenly be at a major disadvantage.
Reliance on (or familiarity with) systemd likewise (if you extensively use systemd, then learning guix will involve learning shepherd too).
Then there are the docs. Nix has a problem there, because of flakes: the official docs barely talk about them, yet a large part of the community embraces them. This makes figuring Nix out a lot harder.
Iow which one is the easier depends a lot on circumstances.