Seems like Farcaster is the perfect place to start trying out some "proof of personhood" type experiements. The moment feels right with frames and the attention it's getting. Maybe @lsankar.eth is working on this in some way?

Small side note: but my favorite formulation of this to prevent scamming is you do some form of hidden KYC, lock up funds in a smart contract, then if you scam the funds are sent to Lazarus Group and your KYC is released

To expand on this a bit more I'd envision some sort of score. There's already some projects working on elements required for this like zkPassport or AnonAadhaar. I don't know the exact recipe to make it work yet but the ingredients are there (or close)