So far the (several) arguments put in favour of prescriptivism seem the old and tired ones, of standards and the importance of communication. An example:
The whole premise of the article is a pandering to the youth with an excuse for their illiterate and malformed excuses for use of the language. As per usual, “you don’t get it, grandpa” is presented as a valid excuse for a lack of education and for football players in university who can’t write a simple one page essay that can even garner a 50% grade.
Enjoy – or avoid!