The statement is trying to say that since our genes are adapted for the Stone Age, it would be ideal for us to revert to the Stone Age lifestyle in order to have optimal health.
It is not necessary that just because we have ‘Stone Age’ genes, we cannot live an optimal life in a time other than the Stone Age.
Returning to the Stone Age lifestyle would mean little to no dependence on the recent technological inventions such as automobiles, internet, mobile phones and the most important of all, electricity. Our way of living would change drastically and this can be advantageous and disadvantageous.
It would be advantageous mainly because everyone would have to do a substantial level of manual work in order to survive. This includes hunting, running, farming with manual tools and swimming. This would help to keep everyone fit and healthy. However, the advantages are very limited.
There are numerous disadvantages with this ideology. We would lose thousands of years of progress and human development. Our technological advancements have enabled us to fulfil our needs.
Firstly, our technology has played a huge role in providing safer and faster medical treatments. The introduction of electron microscopes have allowed humans to study life at the atomic level. By using this knowledge, we have been able to come up with treatments that would not have been possible thousands of years ago. X-rays and MRI scans have allowed us to study different parts of the body and devise treatments according to our findings.
Other than that, farming inventions such as tractors and harvesters have allowed farming on a much larger scale. We are able to keep food demand and supply at approximately the same level. It would be impossible to get sufficient food supply for 7 billion people thousands of years ago. This would only cause widespread famine and chaos.
To conclude, I think that the disadvantages of adopting Stone Age habits outweigh the advantages by a big margin. The statement tries to make an intelligible point but fails to consider the consequences of adopting Stone Age habits.