Answer
Store the argocd-rbac-cm ConfigMap (policy.csv, policy.default, scopes) in Git and let ArgoCD (or the install) apply it, so access-control changes go through pull requests and review. This versions permissions and provides an audit trail of who changed access and when.
Real-world example Granting a new team access is a reviewed PR to the argocd-rbac-cm manifest, not a manual console change.