Heh, I’m so old that I remember when systemd promised that the new init system would be easier to understand than those "vague startup scripts."
Meanwhile, on systems where I don’t use systemd, the entire initialization process can be displayed in about 30 lines on the screen - and I don’t have to wade through a chaotic web of dependencies, some of which are even auto-generated. As far as I can tell, I currently have about 350 of them active.
Boot times were supposed to be fast, too - yet, curiously enough, systemd often ends up saying, "waiting 1m30s for..."