P2P's had a rough, rough time, especially when it comes to crypto and Bitcoin. Long before China cracked down on Bitcoin and exchanges, they were busy clamping down the P2P lending industry there. The big ones globally have also bitten the dust, though some like btcpop seem to have seen some revivals.
More like, they all failed to combat the greedy scammers in the industry. The investors lost their money and some (like me) are still trying to cover their losses.
But okay, based on blockchain? Think there were scores launched last year. SALT was (is?) really successful, but those are blockchain-backed loans rather than p2p lending (you put up collateral for loans). The only one I could remember in addition to suggestions above is Bitbond.
Let it based on blockchain, hashgraph or any other super alien robotic automated lending platform. Without personal authentication and verification, the lending business would never work out.