Thank you for the clarification. I can see from your examples why binary transparency is a useful concept worth considering in its own right. I still suspect there is a huge amount of overlap between the problems the author is trying to solve and they ones that Nix/Guix has already solved (especially the way they want to use a hashing algorithm to identify the release). I'll bet a general solution for binary transparency could be built - a solution from which practically all software in general could benefit, not just Firefox in particular - by building on top of (or at least learning from) the base that the purely functional software deployment model, as pioneered by Nix, has already given us.

I am not simply saying "They should use Nix" as if that would magically accomplish their goals. I am saying that they could build on top of, or at least learn from, the novel techniques that Nix has contributed to the field of software deployment.