It is not enough to believe the person behind that email is Satoshi Nakamoto.
Many accounts of Satoshi Nakamoto can be hacked and to prove the person is /are Satoshi Nakamoto, signing a message with PGP key is a condition.
Do you think "satoshi" will ever just randomly log in one day and post something?
His account is locked, so no. If he wants to claim his account, he'll have to contact me with a PGP signature.
In 2014,
Hacker Hijacks Satoshi Nakamoto's Email, Threatens to Reveal All.