openshift-controller-manager is currently installed using a DaemonSet to ensure that there is an instance on every control plane node.
This has negative performance impact on installation and upgrade due to the semantics of how DaemonSets are managed.
A Deployment with sufficient anti-affinity rules should be used instead to improve the performance of installation and upgrade.
The operator should also ensure that the correct number of replicas are deployed for single-node topologies.

Version-Release number of selected component (if applicable): 4.10

Additional info:

Before this change merges, a backport to 4.9 must be opened that removes the Deployment and restores the DameonSet.
This is necessary to ensure that we don't break the OpenShift control plane when downgrading a cluster.

This issue is related to Bug #2026488. Because OCM is deployed with a DaemonSet, the rollout results in a significant number of SuccessfulDelete events that get aggregated together. Deployment's semantics are better in this regard, as each rollout is managed by a ReplicaSet.