The article is full of dishonest nonsense. It compares file sizes without comparing features. Well, actually it’s blatantly lying by saying that the setups have the “same functionality” when they clearly do not. For example, systemd-homed supports encrypted home directories which is potentially a useful feature for shared PCs, but the non-systemd setup uses nothing for managing /home, so it takes 0 bytes. NetworkManager has a size of “N/A” apparently. It looks like there should be notes or citations but they’re missing. They’re archived here if you’re interested, but it’s just a bunch of upstream URLs; this doesn’t show us what the author is comparing.

The other related point is also nonsense:

We can evaluate the “systemd isn’t monolithic” claim based on how it’s packaged and distributed.

Well, no. We can evaluate how distros package systemd, not what systemd is or isn’t. The author uses Arch Linux to show that a systemd-based setup requires 36MB. But as the article itself states, arch linux puts every single binary into a single package. Not mentioned in the article is how Arch Linux also bundles other stuff most people don’t need in the packages, like header files, programming manual pages, completions for various shells, default configurations not part of systemd etc. Is the non-systemd setup done in the same way or is the author manually installing 6 executables and calling it “equivalent”? We can’t know because one the one side we have a real (worst-case) example of Arch Linux packaging systemd, and on the other side we have “to get the same functionality without systemd, a distribution could use”.

None of this illustrates any waste of space on the entire Debian Stable mirror if you’re worried about that. In fact the bundling of systemd component into a small number of packages saves space for Debian (though it potentially wastes space for your PC).