While trying to implement pod topology spread constraints [1], the cluster-wide default constraints cannot be specified. As of now OCP seems to support only pod level spread constraints whereas K8s supports cluster level default constraints [2].

[1]. https://docs.openshift.com/container-platform/4.7/nodes/scheduling/nodes-scheduler-pod-topology-spread-constraints.html
[2]. https://kubernetes.io/docs/concepts/workloads/pods/pod-topology-spread-constraints/#cluster-level-default-constraints

Cu will require this feature as it will be difficult to set this at pod level as they will have to modify a huge number of deployments.