If you've turned to a system based on everything being perfectly declarative and reproducible, why would you then add an imperative autoupdating system on top of that? Of course you can, but if you're fine with that kind of system, why would you have turned to guix in the first place? It's not like it's just the popular default and you want to do something else on top, it's a super niche thing based specifically around this and you're breaking the core philosophy