Problems with Systemd and Pulseaudio
I find the technical design, configuration flexibility, single syntax, and tooling for analysing configuration and actions to be far superior to the alternatives especially on more complex systems.
I say that as someone who was originally set against accepting systemd at all and resisted it for a long time.
I've come to discover that in the main the problems attributed to systemd are more due to distributions adopting it before it is ready to take over the duties of other daemons, in that it hadn't reached feature-equivalence with the disparate services it extinguished.
Pulseaudio suffered the same way - it was introduced by maintainers before its features were complete for many mainstream use-cases, even though it was doing more sophisticated things without user intervention (I recall one such being automatic up/down sampling to match bit-rates for sources and sinks). In the case of Pulseaudio many people tend to forget that before it arrived the ALSA tooling it replaced didn't support multiple applications using the sound output at the same time, and that issue was a very big cause of desktop user bug reports and complaints.
With systemd one example is not supporting key-files for encrypted file-systems but it replaces the working cryptsetup scripts. That's something the distro maintainers could avoid by not including the systemd-cryptsetup service.
The reasoning behind the missing feature is technical perfection. There have been several pushes to add functionality but Lennart has held out against band-aid solutions and wants a once-and-for-all design which utilizes the kernel key-ring for handling the encryption keys.
So part of the problem is systemd-cryptsetup not implementing the full set of what I'd call 'standard' features but the distro maintainers enabling it, therefore causing regressions in user experience.
It is possible for distro maintainers to build only selected modules of systemd so that where features are not yet comparable the original service could remain, but mostly they don't do that.