I'd be surprised if we manage to reverse deterioration in such a complex system as the human body, especially in the brain, in our lifetime. We are barely scratching the surface, trying to understand the most basic interactions between this massive amount of variables of which we can only control a few reliably.
The problem is conceptually quite simple:
Ageing is an accumulation of degradations in our DNAs.
We just need to reset/monkey patch our DNAs with a prior younger version through CRIPSR + viral vectors.
The only issue is the scale of the gene therapy (changing whole organs) but I'm quite sure it is doable, just underresearched/underfunded.
1 March – Scientists use lipid nanoparticles to deliver CRISPR genome editing into the livers of mice, resulting in a 57% reduction of cholesterol levels.[160]
Rejuvenation is not science fiction, it just require funding but expecting this from humanity might be considered science fiction and the situation isn't going to improve given than the Flynn effect is reversing..
