Parent is referring to Agnost's own concept of Containers, which are a different concept and further overloading the term. I agree with their take that this is confusing. Your Agnost Container is an abstraction over several K8S abstractions over actual containers.
https://agnost.dev/guides/containers/
Strictly speaking, k8s deployments describe a number of pods, and pods describe a number of containers. So creating a deployment in k8s could result in the creation of many containers as a result.