pulseaudio is currently built with option:
Disable optional systemd daemon (socket activation)
I've not had the time to investigate/test enabling this feature yet, but opening this bug to track such efforts.
* Fri May 06 2016 Rex Dieter <email@example.com> - 8.0-7
- use %%tests macro, enable systemd socket activation (#1265720)
Tested mostly harmless, I don't think it's used by default, and doesn't seem to interfere with pulseaudio's own autospawn behavior