Well, systemd is great for responding to events (like devices and networks going up/down) so it seems like a good fit for embedded/IoT. If anything it'd be bad

Well, systemd is great for responding to events (like devices and networks going up/down) so it seems like a good fit for embedded/IoT. If anything it'd be bad for servers since those are (usually) basically a couple of services and daemons brought up at boot and not changed during runtime, with a few interfaces that never change. Systemd is not that heavy to run when configured correctly (which is what the distro should do).