The operator creates a number of resources, which are not managed by any install system (*-operator.yaml, olm csv.yaml) and need to be removed manually after uninstalling the operator.

• <operator-namespace>.servicemesh-resources.maistra.io ValidatingWebhookConfiguration
• istio-node DaemonSet in <operator-namespace>
• istio-admin ClusterRole
• *.istio.io CustomResourceDefinition
• *.maistra.io CustomResourceDefinition

Cluster admin will have to do most of this work:

• oc delete validatingwebhookconfiguration/<operator-namespace>.servicemesh-resources.maistra.io
• oc delete -n <operator-namespace> daemonset/istio-node
• oc delete clusterrole/istio-admin
• oc get crds -o name | grep '.*\.istio.io' |xargs -r -n 1 oc delete
• oc get crds -o name | grep '.*\.maistra.io' |xargs -r -n 1 oc delete