If you have a working config, thats exactly the point. Before you built your config, you don’t know. If you deploy silverblue, you know it will work beforehand because exactly this config, including /etc, has been tested upstream before. What you are to your buddy, Fedora Atomic is to me. The difference is, it is not just one person that tested some config they decided on on their single piece of hardware, it is the effort of a full blown distro team.
That power efficiency is a direct result of the instructions. Namely smaller chips due to the reduced instructions set, in contrast to x86’s (legacy bearing) complex instruction set.