Just to reiterate, yes, there is. A NAS is not a DAS. It should work (and does, if you configure it correctly), but it adds many layers of complexity that are completely unnecessary for that application, introduces many additional points of failure, greatly reduces performance, and unnecessarily burns a lot of watts.
Well, it's implicit in this section of the manual:
Provides information on how to create Server Message Block (SMB) shares on your TrueNAS.
www.truenas.com
And most guides will have you create a user for your share. See, e.g.:
www.familybrown.org
Sharing as root is a Worst Practice that never should have been allowed.