For Airdrops KYC is OK but i do not  recommend for the ICOs as we dont have a guaranty that the coin comes to the market and have a place for a long term , the KYC are the data people , and  people participate from many countries and the data can be sold for a good amount and they make profits and the ICO may vanish in a night and its just a waste of time working for ICOs. better we give for Airdrops for coins that have stand in the market.