That advice more and more doesn't work in this day and age. Though it's a good goal, just not that achievable

What's the reasoning for this strategy? Is the idea that it's harder to retain a salary job if your older (I'm assuming because you are likely more expensive and a target for redundancy)?

For a lot of us, the work we do is meaningless and takes us away from what we would enjoy doing with our limited remaining years. It might be a good strategy to find meaningful work but it's unlikely to compare favorably to spending time with ones family (for example).

This only works if you can afford it, of course.