ZD, I just reread Sam’s post – I had thought he said the opposite.
In any case, the fact that Sam wrote it doesn’t necessarily make it true, plus, there may be other opinions. Also, even if R’Elyashiv said that, I wonder if he could have been referring to the world from the time of Adam’s creation (i.e. after the 6 days of creation). Maybe we only start counting the 5776 years from that point, and that is what R’Elyashiv was referring to.