Bitcoin is not only a work around for Sybil attacks. That'd be hashcash by Adam Back. Please do your homework. Bitcoin is able to settle transactions in an ano

Bitcoin is not only a work around for Sybil attacks. That'd be hashcash by Adam Back. Please do your homework. Bitcoin is able to settle transactions in an anonymous and open network of participants without byzantine-faults. A naive implementation of a ledger cannot do that. Neither can data bases. That's why some find Bitcoin useful.