Ultimately, my workplace setup is what has the most gravity. And the most I can get most workplaces to standardize on is Homebrew for package management of off-the-shelf software. Nix is so far outside of the wheelhouse for most engineers that I can't even propose it. It would be too much of a distraction for too many people for too long that it's just not seen as worth it and it's not worth spending the political capital on the attempt. Employers would literally prefer to run scripts from a whitewashing, barely-auditable Jenkins instance with parameterized jobs than to attempt to figure out how to distribute portable scripts and get everyone's permissions working.
So I need to pick software that will cooperate with other tools in an unstable fashion, rather than software that attempts to fully and exclusively control the environment to provide guarantees. Chezmoi fits. Nix and home-manager do not.