Which is more than what we can say about Jesus. Name a single eyewitness of him while he was alive who recorded it. Paul admits never seeing Jesus while he was alive, the twelve wrote no books, the Romans have no notes on the events. No one who supposedly saw any of the events managed to find quill and parchment. And what's more no one who heard second hand during the events recorded it. The Gospels are clear that news was spreading all over Judea and yet people writing about other would be Messiahs and political rebellions are silent about Jesus.

Besides, and again this important, Socrates is a consistent believable story. We don't have multiple versions of his life that all go against each other, often within the same text.