The claim was about efficiency, not just power draw.

In your comparison you talk about software compatibility, but the Mac can run Linux and many open source tools & apps found on it. So the Pi is only ahead if you arbitrarily limit the comparison to a specific distro that's not Asahi or an application like sxiv, and in addition are the kind of user who wants that software and doesn't care about Mac exclusive programs. Which is valid, but has nothing to do with a metric like power efficiency.