@nullius I think you have too much faith in the goodness of humanity. 
Of course you may be right but you have to look at where you are and what often goes on around here and in this world (forum world not geographic world). User in question recently changed email which can possibly also mean a hacked account. Do any of his/her previous posts have such altruistic discussions on protecting all of Bitcointalk humanity? The PM's in question seems way out of character for the posters past conversations. But I guess one never knows.
Of course you may be right but you have to look at where you are and what often goes on around here and in this world (forum world not geographic world). User in question recently changed email which can possibly also mean a hacked account. Do any of his/her previous posts have such altruistic discussions on protecting all of Bitcointalk humanity? The PM's in question seems way out of character for the posters past conversations. But I guess one never knows.