This can go two ways...
one being not secured, and the result of mass-user identity theft, the other being a revolutionary step in identity verification without invasion of privacy. I hope the latter.
We avoid the leak from the beginning,Usechain will not keep the user's privacy,the users keep it themselves,usechain only keep the mapping relationship between real-user and their on-chain account,Usechain can help the government find out who the on-chain account belonging to if the government have the proof and certify like search warrant in real-world,as you know,for example,when you're booking a hotel room,the hotel doesn't need your telephone number and your name,all they need is the unique on-chain account and criminal record(if it exits)