This article is mistaken from the get-go as an operator is not the same as an apiservice. Rather an operator is a wider term for something that includes a controller. See https://kubernetes.io/docs/concepts/extend-kubernetes/operat...

Also it's important for people reading this article - an apiservice (which this article talks about) is very rarely something that should be done. An operator is more appropriate for nearly all cases except for when you truly need your state stored outside of the internal Kubernetes etcd datastore.