I'm someone who very much loves the concept of Nix and what it is trying to achieve. However, a sibling poster put it well:

On the advice of numerous HN threads, I switched from Homebrew to Nix, and gave it a 6 month shot. Nix was great at first: simple, fast, elegant. However, I quickly realized that the simplicity was a facade that even a casual user would eventually be forced to remove. And what you find behind the facade gets really, complex really quickly.