GL369 - As of 6.3, Permissions for asset reports were managed under [1]. By default, dam-users and mp-contributers were the only 2 groups that were denied the permissions to view asset reports.
Starting 6.4, report functionality has been moved to [2]. So, you can manage permissions for Asset Reports by allowing or denying permission to the path at [2]
[1] /libs/dam/gui/content/nav/tools/assets/assetreports/rep:policy/deny
[2] /libs/dam/gui/content/reports