Sure, docker-compose is great, but could we get similar functionality using just the tools that are built into CoreOS? Can we get automatic updates, too? Yes we can! 📦
I prefer the simplicity of docker-compose on top of podman myself for my self-hosting needs, but I imagine systemd integration to be advantageous in many ways. You can have your containers activated by a socket. You can configure your containers so that they depend on certain system services being up or available, giving you more fine grained control over your start up process. That's just off-the-top of my head as I have very limited knowledge of this aspect of podman, but I don't think it's meant as a backup. It just provides a more flexible solution for certain deployment scenarios, in exchange for more configuration complexity of course.
I prefer the simplicity of docker-compose on top of podman myself for my self-hosting needs, but I imagine systemd integration to be advantageous in many ways. You can have your containers activated by a socket. You can configure your containers so that they depend on certain system services being up or available, giving you more fine grained control over your start up process. That's just off-the-top of my head as I have very limited knowledge of this aspect of podman, but I don't think it's meant as a backup. It just provides a more flexible solution for certain deployment scenarios, in exchange for more configuration complexity of course.