I don't think this act means foreigners by any means, they just wanted to regulate the market of Sim cards as it used in many illegal activities without knowing who is the owner, so they ask the buyers to have Ids in case of buying new numbers. Foreigner can easily head to the big branches of communication companies holding their passport just as before.
Sure live out of the campus as the campus dorm conditions is miserable.If i were you I would not even choose Yunnan university to study Chinese. Almost teachers there unqualified with accents and never speak pure Chinese. Traditional ways of teaching and boring classes.