You need 3 nodes for a high availability control plane if you’re managing the Kubernetes control plane yourself. With GKE, the control plane is totally managed

You need 3 nodes for a high availability control plane if you’re managing the Kubernetes control plane yourself. With GKE, the control plane is totally managed by Google Cloud, things like etcd etc are not running on any of your instances. It’s fine to have just 1 compute node (like the before state), or to put all the k8s control plane on a single node (like the after state) if you don’t need high availability.