It's like I'm in a hall of mirrors......
It's the integration of systemd, the common approach that yields the giant payoff. I understand the "lots of independent utilities" Unix philosophy but systemd's consistent broad scope yields increasing benefits.
See also vim vs Emacs.
I think there are other reasons why people dislike systemd (and recalling a few articles with people ranting about it; I think there are many around), and usefulness of standards and alternatives/choice wouldn't necessarily make sense either, but here is at least one of the ways to view it.
As for init scripts, I think it can be even a bit nicer than that, since systemd provides some backward compatibility with sysV-style init scripts [1], but in that systemd acts almost like a swappable implementation.
[1] https://www.freedesktop.org/software/systemd/man/systemd-sys...
Well, but then you must be aware that you are leaving lot of effectiveness, unification and deduplication on the table.
See, many people think of systemd as if it was init replacement that grew timer support too. They are looking at the wrong level of abstraction: it is an event machine, that manipulates units when events happen. That event might be boot to certain runlevel, timer, hotlplug, incoming request on socket, dbus activation, whatever.
By cutting and dragging out one of the event handlers outside into special-cased, custom flow component that duplicates existing functionality anyway, you are ending up with a worse system.
But this still makes no sense. You can just develop another thing that converts from the systemd format to something else, or make the other daemon capable of loading the systemd format directly. It isn't even hard to do this, I've seen various things do it. And depending on where you are the systemd formats are arguably more standardized than old crons and sysloggers in the current year.
Plus, it creates fragmentation instead of concentrating efforts on one project.
It's easy to get situations like "I need feature F but that's only in B, we use A because C needs it".
Use of any features outside the lowest common denominator quickly makes things nonswappable.