diff --git a/lib/private/User/User.php b/lib/private/User/User.php
index c3d8af6f358df..ff357a3badbfa 100644
--- a/lib/private/User/User.php
+++ b/lib/private/User/User.php
@@ -416,7 +416,7 @@ public function canChangePassword() {
 	 * @return bool
 	 */
 	public function canChangeDisplayName() {
-		if (!$this->config->getSystemValueBool('allow_user_to_change_display_name')) {
+		if (!$this->config->getSystemValueBool('allow_user_to_change_display_name', true)) {
 			return false;
 		}
 		return $this->backend->implementsActions(Backend::SET_DISPLAYNAME);