How do we know that lots of people didn't figure this out & then got on with their lives? Because there was no way for them to tell all the other people in the world, we'll never know, or if they wrote it down it's been lost, so likewise we'll never know.
Is hard to imagine what the world was like before mass literacy and mass communication.
Yeah, shout out for rsync also. It's awesome. Combine it with ssh & it feels pretty secure too.