Well, it's both. It's both packaging and deployment. Which is convenient, but probably a mistake. Docker is decent at being a packager, but rather terrible at deploying stuff, which is why we have better, high-level orchestration systems like Kubernetes that handle deployment the way it should be done, and reduce the Docker runtime to a mere container runner.
That is a fair point, and most of the end users we work with are using k8s and mesos to deploy and run the applications. The issue I have with the article is that it assumes that a packaging tool is what defines the rest of your operational procedures. They are two different things, as they always have been in Linux.
