You can create protected resources for all tags and subtag categories.
Simply create a tag or go to your tags menu, at the upper left corner you will have an option to select “Protected Sources” - choose on or off.
A protected resource can be used to limit or extend access to tags and tag categories in addition to the user role, this can be managed under Users and Roles.
To control protected resources go to settings and then Users & Roles. Find the user, either via scrolling through the list or typing their name or email address in the filter user section, then enter the user profile.
You can choose to allow full access, access for the entire tag and subtag category, or specific subtags.