if most participants are not willing to do KYC they can join other projects, they don't like to join KYC bounties because they can't multiple accounts
One of the advantages of kyc for bounty is that it serves as a control measure to limit the creation of multiple accounts for the bounty. Bounty hunters are fond of duplicating their accounts to secure more stakes in the campaign, when a kyc procedure is enforced, it leaves them handicapped because rewards wouldn't be received without completing the kyc.