Isn't the term "epigenetic" about non-DNA information, like in mitochondria etc, i.e. not something recoverable by just scanning DNA more precisely? If so, it doesn't seem reversable?
Those molecules can get out of place, and not line up correctly anymore. This research shows that that's a major cause of aging, and that it's possible to reverse it.
The theory here is that as we age the cells epigenetics fuzz out, so that skin cells start to look a bit more like neurons and other cells and vice versa.
In reality, it will probably just mean a bunch of snake oil 'epigenetic health supplements' on the shelves that don't actually do anything.
You can't just fix the DNA, it must also figure out whether it should become a hair follicle or one of the many subtypes of cells that make up your skin layers. We know that this differentiation seems to be controlled by ion/electrical signals early in life.
So a key question is: Why does differentiation accuracy seem to degrade with aging, and is there anything we can do to stop it?
CRISPR is pretty good at fixing DNA, we definitely need to optimize our use of that tool but at least there's a path. We really don't have a clear path to fix the differentiation/epigenome problem.
A lot of it is just part of normal development.