This article in The Economist neatly expresses what we often bang on about.

“Most companies are remarkably ill-prepared. There was a flicker of interest in the problem a few years ago but it was snuffed out by the recession. The management literature on older workers is a mere molehill compared with the mountain devoted to recruiting and retaining the young”

This is reality. It is not just about ‘preparing for an ageing workforce’ (like you might for Y2K in the hope that it never happens); it’s about MANAGING an ageing workforce.
The ‘molehill’ of management literature on managing an ageing workforce compared to the ‘mountain devoted to recruiting and retaining the young’ also reflects budget allocation by most organisations. In a word: CRAZY.

I’m not sure it is as difficult as The Economist makes out. It just requires a different mindset.