If you do, you will get an Operation could not be performed error. AIX ACLs are not recognized and not supported. Security auditing is not accountable to any individual user actions through an SMB client. If auditing is turned on, some audit log event entries will have the root identity. Disk quota and ulimit of any user is not checked.
Any user can fill up the shared file system.
There is no log information about which users are connected to the AIX server through AIX Fast Connect for Windows. But windows clients always send in a format that needs no controls.