The Jira KEYCLOAK-15142 has been closed without an official statement on the subject.

Basically, the behavior mentioned in the Documentation seems to be a bit counter intuitive:

You can only create or delete realms by creating or deleting the YAML file, and changes appear in the Red Hat Single Sign-On admin console. However changes to the admin console are not reflected back and updates of the CR after the realm is created are not supported.

The part stating "updates of the CR after the realm is created are not supported" could leave customers confused when editing the CR and not seeing those changed applied:

1. Could we review this behavior or have an official statement on why it's configured this way and customers will always need to delete + re-create the KeycloakRealm CR?
2. Are there any plans to modify this behavior?

Deleting and re-creating the complete Realm is not feasible as it causes downtime if adding a new client or performing another operation.