node.spec.unschedulable is a leftover from early k8s days when taints and tolerations didn’t exist yet https://github.com/kubernetes/kubernetes/issues/69010.

 It only still exists because removing it would be a node API change. It is responsible for triggering the addition or removal of the Kubernetes unschedulable taint. The scheduler only looks at taints and we don't need to add another taint node.kubernetes.io/unschedulable:NoSchedule with NoSchedule effect after (RHWA-511) medik8s.io/self-node-remediation:NoSchedule