> Also, the organizations that somehow couldn’t figure out how to use and maintain traditional init systems were the ones that produced the current generation replacements and pushed them so hard.
This is revisionist. The organizations that built the current generation were those who had to support those who couldn't figure out how to use and maintain "traditional" init systems. Distro init scripts were (usually, and at great effort) decent, whether from Red Hat, SuSE, Debian, etc. (just don't ask too hard about why they were different). But the third-party (often, but not exclusively, proprietary) software vendors looking to support even a single distro were godawful. Eventually the support burden for e.g. Red Hat got large enough it made more sense to replace it wholesale than keep mentoring the latest batch of e.g. Oracle interns in how to write half-decent shell scripts.
If you spend an afternoon installing it and configuring a few network services, you’ll already know most of what there is to know about how init used to work.
It used to be extremely elegant and robust.
The main flaw in the design was that the “service” files were written in a Turing complete language, which meant that distribution maintainers could ship things that were arbitrarily terrible, and many chose to do so.
(Edit: Also, the organizations that somehow couldn’t figure out how to use and maintain traditional init systems were the ones that produced the current generation replacements and pushed them so hard.)