In the spirit of "Do one thing and do it well", systemd's goal is "manage services and dependencies".
If it was it wouldn't include its own DNS server, or it's own timeserver, or it's own logging infrastructure.
The problem with systemd and the whole Freedesktop crowd is that they are trying to solve problems that do not exist anymore. For example you now have hugely complex systems just to make sure your soundcard will only be usable by users logged in locally. While this is, in theory, a great security benefit, most machines today are single user. So in effect it's lots of code that's useless at best and a potential security problem at worst.
Everybody goes through a phase where they think they can re-invent the world and design something cool and complex with the technologies they have just heard of. In the past only large companies could afford such an effort. Microsoft, for example, implemented many of the "new" ideas in Windows. This is why you have things like OLE with it's offspring of OLE automation, or a logging system nobody uses because it's essentially unusable. Windows being so unusable, particularly in the 1990s, was a big push for Linux for "serious" applications.
Now we have a new situation, it's "fancy" to have some work on a Open Source project on your CV, that's why there's a huge pressure for mediocre and bad developers to do something with Open Source. Those mostly are people who still having gone past their "coimplexity is good" phase and don't understand yet, that it's not a good idea to require 5 daemons in the background just to have a GUI running.
Ideally we should take a step back and look at what we _really_ need. Do we really have to have such a complex service management system? Shouldn't it be enough for a desktop system to just have a single shell script booting up X and the window manager and setting up the network? Why do we have a wireless subsystem that needs a "wpa-manager" just to set up the keys to encrypted networks? Why do we have a modem manager that reliably is unable to access your cellular card after a upgrade?
Have you ever tried to write your own minimalistic init-system? I once turned an old SuSE installation into an X-Terminal. It took a shell script of 5 lines and it booted in a few seconds... on an Pentium 90! You can get much faster if you cut all that crap you don't need.