I'm planning to move over to Guix over NixOS, as soon as my current situation improves and possibly import a new libre respecting laptop (Star Labs is thankfully available in India). I do have a very old laptop with a Celeron processor and 4GB of RAM with Guix installed already, and what has come to my attention is that it uses shepherd.
I'm not actually against or for systemd, in fact, I am not really sure why I should even care - maybe it is because I'm still not on to the level of a power user. Since I'm starting to learn kernel basics to prepare for GNU/Hurd contributions in the nearest possible future and shepherd seems to be what the GNU folks will be using, is there any reason why I should even care about the freedom of init system?
Edit: I'm asking this because I came across this blog - What is systemd and Why Should I Care? and also because Guix uses shepherd, and I'm not sure how I'll be affected.
To imply that systemd is merely an init system is ingenuous at best and dishonest at worst - systemd is so much more than an init system, as that article mentioned. Since the article was written in 2014 systemd has grown massively in scope, even more than the author feared.
It manages DNS, home directories, system services, seat managment, cron, system logging, booting... the list is ever growing. As such many people fear it is becoming too dominant through making more and more software dependent on it. It is not atomic - it is very difficult to have just one piece of systemd as its parts are tightly integrated and inter-dependent.
One could even claim that systemd failed in it's original remit - to make startup as fast as macOS by running tasks in parallel and by deferring service startup until they are actually needed. The result has been a not very performant init system - many init systems are faster eg runit, dinit. The systemd people now claim that speed is not a design goal.
It is, however, open source and very widely adopted. Most people don't care - they just want to run their browser and word processor.