Maybe this statement actually holds in reverse?
Quoting vbernat's comment on Lobsters:
systemd was a "gift" for people running alternative desktop systems. Previously, many services were bundled with GNOME and you had to go through many hops to use them on a non-GNOME desktop (for example, GNOME Power Manager). systemd replaced many of these GNOME-only piece of software that were constantly breaking when you tried to use them outside of GNOME. Alternative desktop environments didn't need to write their own version of system-related tools.
So, while this may be seen as centralization, I don't think we would have seen so many desktop environments without systemd. In the past (15+ years), systems were simpler and there was not many things to abstract.
https://lobste.rs/s/gfbpgq/flatpak_will_depend_on_systemd#c_...
That is a good point but it isn't mutually exclusive with the idea that systemd ought to be a standardized API as opposed to a reference implementation without a standard.
Also despite all its convenience it's not without its drawbacks. Among other things you can no longer just launch a daemon from a chroot now you need a full blown container sporting its own init.