Well, another reading of the Article is that if you are an Elector, any wizard you employ must have these privileges, and if you are not an Elector who is trying to employ a wizard, you are not obligated, but you do have to up your game to match it because Article 12 gives wizards the freedom to choose their employer, with the exception of the military (Article 9), the Emperor (Article 10) or against the forces of Chaos (Article 15). If you were a wizard, who would you pick to work for—the guy who is obligated to treat you like a noble, or someone who isn't. Sure, you might not always have that specific option, but you do have the option to leave and find someone who's going to pay you more, and Article 12 sets a soft "minimum wage" that you can haggle with.
"Give me the privileges in Article 11."
"I'm not obligated to give you those."
"Then I'm not obligated to work with you. Good day."