Every government have their own regulation and i think it just to protect investor from china. Too many airdrop sometimes not good for the price in exchanger and its make investor losing money. Maybe China government want ICOs focus the real project and not giving airdrop to protect their investor from dumping price in market
It is not surprising that they have this kind of move because they are already against cryptocurrency in the first place. Trading cryptocurrency for them is illegal so it would already be assumed that anything that involves cryptocurrency would be illegal for them although it is ironic to think sometimes that there are still mining going on in there. One of the reasons why bitcoin price is always going down before is because of China news and there movement against cryptocurrencies so a news like this would not have a major effect in the news anymore.