Lots of people receive death threats and even more claim they receive threats or perceive types of loud criticism as threats. Being on the wrong end of these is no picnic but it is not, in itself, a substantial risk of harm. And again, his own efforts to protect his identity seem to have been relatively superficial. He just didn't think he was going to end up in the NYT and he was mistaken. As I said elsewhere, it's a bummer this is a disruption for him but it's not obvious we (let alone the journalist who actually figured out his name, as anyone wishing him harm could have) should take the claims of risk of harm at face value.