How times have changed! Society used to think very simply (in black and white). When television showed us the world in black and white, that seems to be how we saw the world,...very simply (no real imagination or creativity [compared to modern society). How could we so easily be fooled that these performances on stage were not lip-synced? Maybe it's just that the times made it easier for us to be satisfied with the way things were.
It's not just computers that have opened our eyes, but COLOR television and color photography because now we no longer see the world so simply. It seems that humanity is alot more simple than we would like to think we are. The cars of the 1940's and 50's used to be puffy like children preferrred their toys to be. The world was simpler (of course theose times had their drawbacks) and it was much simpler to enjoy life.
Frankie Valli & The Four Seasons - Big Girls Don't Cry
This video is 3 minutes long (clearly lip-synced, but probably nobody cared).
but humanity was always a 'simple people' with other forces available to control us if we decided to be controllable (lack of character).