I believe the takeaway is exactly that. We are in a situation where we can’t know for certain. We can’t go back in time and learn if there was cheating going on

I believe the takeaway is exactly that. We are in a situation where we can’t know for certain. We can’t go back in time and learn if there was cheating going on. But we can go forward and increase security so the next time we are more likely to be confident about if cheating happened or not. And that is what Carlsen is asking for.