Compose is just a declarative syntax for your stack. Ironically it's not composable. In other words, it's not a package definition--you can't ship a compose file that will "just run" anywhere. For example, most web apps require a database, but you don't want to run one database per web app. How do you write a compose file that says, "use the system postgres if available, otherwise spin up a new one". It also totally punts on secret and config management.

Helm is the closest thing to a package manager for Docker, but it targets Kubernetes, not vanilla Docker (and k8s is overkill for a single server, at least considering the time/expertise required to stand up a productionized k8s installation).