Requiring a restart is a Windows trait. I was hoping that my Linux installations would be better than that.
Er quite, though I was specifically referring to restarting PulseAudio, which takes a second not the entire computer. If the base underlying init process needs a restart, well, that's a different kettle of fish.
FWIW, the only time I restart systemd is to update the kernel, or I guess systemd itself (though the kernel changes more often and thus I can usually lump the latter in with the former). If you do live-patch your kernel, then you can do the same with systemd - it has a command to re-exec itself while preserving state.
I'm sure it isn't perfect, but it is as robust as anything else I've used on Linux. There are fairly few daemons that I've never seen need a restart sometime in the last 10 years.