I'm a bounty Hunter for almost 2 years now and as far as I know only GCOX is the only project that even the bounty hunters need to pass the KYC, good projects like Temco did not require KYC
There are several projects who require you to do KYC, for example LBX, Hara, and so on. It really depends on their legal standings and more complex issues which might be reasonable or just simply a way to filter out sock puppets. Temco and GCOX bounty was handled by the same bounty management (their admin on Telegram is the same in fact).
Just a suggestion you might want to follow Telegram channel of any bounty that you joined in, because sometimes they don't update the thread but they make an announcement on Telegram.