You seem to have overlooked the crucial point in Nikhil's essay - namely, that when we're asleep we have no control over what's going on or what happens to us. While it is true that our body and brain are undergoing changes while we are asleep, this does not change the fact that there is a lot of mystery surrounding what goes on during those three minutes.
It may be true that sleep helps us regulate our appetite, grow and develop, and improve our physical and mental health - all of which are certainly important - but the fact remains that we are still not consciously aware of what transpires during that time. We can be sure that our body and brain are working hard, but we cannot be sure of the exact details of these processes.
Furthermore, while sleep deprivation can have serious effects on our health, this does not mean that the three minutes of sleep are any less mysterious. Sleep deprivation or not, three minutes is still a short amount of time, and yet it can be enough to restore and repair our bodies, regulate our hormones, consolidate memories, and process emotions - all without us being consciously aware!
In conclusion, there is still a great deal of mystery surrounding our sleep and what goes on during those three minutes. While we may know some general facts about the benefits of sleep and how it affects us, we cannot be sure of the exact details of what goes on during those three minutes. It would be wrong to say that nothing “the hell is going on”; in fact, something amazing is happening in just a few small moments that we simply do not understand!