This being selfhosted is exactly the reason I would’ve expected people to be aware there’s more variety out there. systemd is not as ubiquitous as you make it sound.
Secondly, tying your containerization solution into your init system is a spectacularly bad idea. You could already tie containers into systemd units, quadlets just make it easier; but the best practice advice is to not do it at all. You have a restart policy built into docker/podman for a reason. Let the init system deal with podman/docker itself, and let podman/docker manage their containers.
Third, the article title is misleading; if anything it should say quadlets made them give up podman-compose, not docker-compose. There’s no reason to reference docker in this article — unless you’re doing it for the views.