The wolfi-base metapackage includes busybox, ca-certificates-bundle and the package manager. The change is to make the use of base-builder image more flexible.
Instead of using Wolfi base images from cgr.dev and making that mess on the Dockerfile, why don't we build the base images ourselves from Wolfi repos with apko? The intention of this is to simplify the main Dockerfile and avoid having to patch the base image every time, it also simplifies some steps like image ownership management and provides extremely fast builds.