This is one of the comments from this thread:

This sort of video while purveying a set of facts completely misleads the viewer by confusing regeneration at the cellular level with structure at any scale larger than the cell, at the organic or whole body level. It is at these scales larger than the cell that decay happens, can not help but to happen, is guaranteed by the second law of thermodynamics, and results always eventually in death. No amount of medical advancement will ever fundamentally alter this fact. Doesn’t matter if a being is made of biological cells, or of advanced nano meta materials grown in a lab. Structure decays over time. Most people have been told and believe that your DNA holds some sort of genetic blueprint of the structure of you body. It doesn’t. Not at all. DNA stores zero info about the structure of your body or the arrangement of your cells. DNA isn’t a map or a structural diagram. DNA is a recipe. A self catalyzed recipe. It tells enzymes to do this until that happens and then to do that until this happens and so on until you are you. But it doesn’t know what you are, or even what it is a recipe for. It can’t repair you because it doesn’t know what you are. It only knows how to grow you, and that, only the first time. Cells decay, and cells replace themselves, but every time they do, the arrangement of cells that makes you you gets a little more unorganized and disordered, a little less you. The only way biology can replace a whole animal is by producing another new one... we call them “kids".

Let’s think about what an entity would need to be capable of if it was to repair itself at the structural level. Well first, if you want to keep disorder from piling up, you need to be able to know exactly what your structure is supposed to be. You need to store that data as a reference set. And then you need to constantly check all of your current structure against that stored reference set. Obviously biological entities don’t have such information or the ability to read their own structure and compare that structure to the stored standard description. People often talk of the incredible storage capacity of our DNA molecules. Each of our cells has a copy of the genetic info biology needs to grow a new human. But even the billions of genetic words in our DNA would be absolutely insignificant should biology want to store all of the information required to describe our structure. In fact, the database would by necessity have to be larger than the bodies they describe, much much much larger. And that is just storage. An even more intractable problem would be devising a method of reading our own structure bit by bit such that it can be compared to the stored standard. Measurement is an invasive process. Not because we have clumsy machinery, but by physical causal nature of reality (see Gödel, Turing, and Shannon). And then there is the computational problem of comparing you to the standard. And then there is the self amplifying problem of the inevitable degradation of the data stored in the structural standard. For that you’ll need an endless cascade of other redundant information sets (to check against each other). Now we can talk about a still more intractable issue, that of the inescapable fact that the very process of storage and of reading stored data actively causes data decay. In short, the whole repair project is a physical impossibility. Oh, we didn’t even talk to the fact that there is no physical possible way to effect a repair to the structure of an entity at any scale without introducing even more chaos and disorder.

Evolution is the only solution. Turns out repair isn’t even all that important to evolution. Why, because repair maximizes stasis and evolution is a process that selects for adaptive change as predictive mechanism in an ever changing environment.

Evolution finds ways of insuring the minimal stability required of maximal change.

Ok, imagine that you had a the technology that would periodically replace every part of your car with exact replicas made of brand new freshly poured metal... not from the original factory casting forms and machine tools, but in the exact shape of the used parts as they are after the wear and tear that happens through use over time. What matters more to the aging of your car, the age of the metal it is made of or the wear and tear that use imparts? Same with a biological entity, even should your cells always be replaced by cells exactly as fresh and young as the ones you had when you were 18 years old, your structure would still decay as a result of general wear and tear. As I’ve already pointed out, the very process of cellular replacement is itself probably the greatest source of accumulated entropic structural disorder. Oh, and there is no way to avoid the decay of order. The nature of physical dissipation of structure, described first as thermodynamic entropy and later independently as information and computation and communication entropy is the only known attribute of causal reality that is absolutely universal and independent of domain... is true in all situations and at all scales no matter what materials or forces are at play, is as true in quantum realm as it is of living things and of planets, stars, galaxies, black holes and the entire universe.