> The opposite side of this is that the value of knowledge held by such workers is enormous and getting rid of them because the bean-counters will see a savings

> The opposite side of this is that the value of knowledge held by such workers is enormous and getting rid of them because the bean-counters will see a savings in wages and salaries is counter-productive to the long term health and viability of the company. Ya, i'm not arguing that this is a good policy. Merely that it is a plausible interpretation of the same evidence. It may be that IBM sees the most value in skills that younger people tend to possess (say, React.js coding skill), or that they want to pivot their business in those directions. And those things merely correlate strongly with age.