My answer for this question 30% yes and 70 % no! The reason is whenever i fill KYC for any airdrop, only 30% time it will passed and rest 70 % time i will not get any answer or fail. So according to me, KYC for airdrops are useless. But if we think about it, then it is the best way to track fraudster. I think only bounties should have to apply KYC for participants where KYC for airdrops are not good!
Maybe you are right, but this really excludes most of the scammers and those who use multi-accounts, so I think that KYC is a big plus. And it's also a necessity that the state demands!