Silverblue is intended for the opposite of that. It is single system image mostly immutable root OS. The goal is to *not* tinker with the core OS, and do your tinkering in containers (toolbox, distrobox, whatever).

Complaining that rpm-ostree took 2 minutes to update 2 packages (rpm-ostree downloaded an entirely new pre-baked filesytem snapshot and applied it atomically) is completely missing the point, as is complaining about selinux after swapping out a bunch of system level stuff. This is like the antithesis of the use case for Silverblue, and an author who has somehow never had to build a package for anything but Arch (deb would be much worse) complaining about the difficulty of building RPMs to install/overlay on the host system, which is not the intended use case *anyway*, is silly.