As a business-owner in my mid-40's, I travel around quite a bit. There are locations where the employment picture is similar to what the author describes. But what he describes is far from the norm in the places I travel to, or from what I hear from friends and old coworkers during lunches. Ageism, low-salaries, "sweatshop"-like/highly-political work environments, lack of diversity in companies/economic sectors, lack of interesting problems to solve. All are observations of mine, as well as old friends' concerns voiced softly after looking over their shoulder during lunches over the past year or two.
Very good IT people (programmers/developers, DBAs, infrastructure, the whole gamut) wanting to leave their current job, but wondering where to go, because their friends in other "just as bad" companies are looking too. Discovering they can still get interviews--but maybe not the job--after age 35; and discovering the difficulty in even getting interviews after age 40. Watching their companies hire either H-1Bs for 40-50% of what they're paid, or college interns (or even recent grads for intern salaries) for even less.
Yeah, people would like to be making this much money in technology when their 50. But in most places, it's a pipe-dream.