All of these arguments seem extremely tenuous. You are the one creating the arguments for reading Shakespeare not actual studies or experience. This proves nothing. A teachers job is to teach a subject and part of a subject is quality. A teacher recommends reading based on quality or lack of quality much more than based on social norms. Also teachers don't create culture and power is related to everything humans do. This whole area of study is really not articulated well.
You must go back to the basics of this basic subject. What is the "quality" you seem so sure of? If you had to explain what is "quality" you would be in a difficult situation, when crossing through differente cultures. Even in the same culture, what defines "quality" is much more the political arrangements produced by different mediators than something inherent in the work itself.
