How to hide/turn off/disable DNS Settings menu for a customer in Plesk so that DNS Settings is not visible at all for a customer?
Modify service plan permissions:
Service Plans > plan_name > Permissions > uncheck DNS zone management
This way DNS Settings menu for subscriptions assigned to a particular service plan will be hidden under a customer's account but Plesk admin will still be able to see DNS Settings on a domain. So the menu will be hidden for customers only.