>>xondon+(OP)
But 99.9% of all videos uploaded never gets more than a few handfuls of views so those are irrelevant. Of the remaining 0.1%, you don't need to watch every second of every frame - speeding it through at twice the speed should be doable. So by your own calculations, 72 000 * 0.001 * 0.5 = 36 people working full time.