Job prospects for information workers will be far better than those in physically demanding jobs. People’s bodies give out by 50. Not completely, but enough where they can’t do physically laborious work.

The broader point of the new replacing the old is generally true (your marketability will decline by age 50), but I still see many baby boomers holding onto well paying positions for the foreseeable future. I save to hedge the risk, but I’m not too worried, since I believe the risk is over-stated.