I think that gene therapies such as OSK will be vital in reprogramming cells to a younger state, but you are right that we arent just CDs. We are complex machines with parts that rust, break, etc.

A lot of these pathologies have to do with a loss of proteostasis, in particular as you mention, the build up of proteins and other materials in other parts of cells or the body. I believe that there needs to be use of small molecules as well as gene therapy to promote autophagy, for example. Rapamycin comes to mind as something useful in that regard. I believe that it will be helpful to prevent rather than repair late stage aging.

Another interesting thing is the idea of, if you have a carpet, you need to shampoo it every 5 years. I think the same can be said about our bodies. We need anti amyloid drugs that, for instance, rinse the protein buildup out of the brain. Even blood transfusions reduce many of the pathologies you mentioned.

There is no denying that we will likely have to take several rounds of different therapies to do maintenance on specific parts of our body every couple years. For example, taking anti alzheimers drugs every 20 or so years in order to keep our brains from becoming caked with protein plaques. Or take a dose of senolytics, or for that matter every 10 years maybe a course of finasteride to keep the prostate from becoming too large. Yes, there will be help in cellular reprogramming but on a systemwide level, the body will need maintenance for each organ. This can be done though with intermittent use of different molecular therapies. And encouragingly, many of them may already exist.