Tested on our test server logged in as a staff user without Item Tag permissions with the following results:
Add item tag/tag type: the options to add a new item tag and to add an item tag type were both unavailable (e.g. grayed out)
Edit item tag/tag type: I was able to select an item tag and to edit it, but the update was not saved and an appropriate error message displayed. The same was true when I attempted to edit an item tag type.
Delete item tag/tag type: I selected an item tag and attempted to delete it, but was unable to do so. An appropriate error message displayed. The same was true when I attempted to delete an item tag type.
EG 3.10.3
Tested on our test server logged in as a staff user without Item Tag permissions with the following results:
Add item tag/tag type: the options to add a new item tag and to add an item tag type were both unavailable (e.g. grayed out)
Edit item tag/tag type: I was able to select an item tag and to edit it, but the update was not saved and an appropriate error message displayed. The same was true when I attempted to edit an item tag type.
Delete item tag/tag type: I selected an item tag and attempted to delete it, but was unable to do so. An appropriate error message displayed. The same was true when I attempted to delete an item tag type.