This comment sums it up pretty well: https://github.com/NorfairKing/nix-does-not-guarantee-reprod... (https://archive.is/KKx0V)
Additionally, I find the author's response of "PRs welcome" somewhat unsettling. It comes across to me like a poor-taste joke: someone writes an opinion piece with misleading information, then expects those pointing out the errors to do the work of correcting them.
I would be remiss if I didn't mention Brandolini's law.
A few references:
- A more nuanced interpretation of reproducibility vs repeatability: https://discourse.nixos.org/t/nixos-is-not-reproducible/4268...
- Reproducibility rates on Nixpkgs: https://arxiv.org/abs/2501.15919