You can programmatically deactivate vSphere IaaS control plane on a vSphere cluster by using the vSphere Automation REST APIs.
When you deactivate a Supervisor, the vSphere Kubernetes Service forcefully deletes from the cluster all objects and configurations part of the Kubernetes infrastructure. To deactivate Kubernetes workloads on a cluster, Use the POST https://<vcenter_ip_address_or_fqdn>/api/vcenter/namespace-management/clusters/<cluster_id>?action=disable
request and pass the cluster ID as a path parameter.