I think he's saying things are more volatile now. When the industry was much smaller, it was easier to make and stay in personal contact with others. Also, it's natural that if you started your career 25 years ago, many people you've met back then (and may have also started back then) are now senior (devs, managers, etc.). A person that started in the industry in the last 5 years may not have many friends in senior positions, and personal connections are more volatile as well (more people, more competition, etc.).

It's my reading!

To clarify - a random SWE's random peer from 25 years ago is much more like to be in an influential senior position, than a random SWE's random peer from a job 13 years ago, or a random SWE's random peer from a job last year.

Your friends are statistically more likely to be closer to the top of the pyramid than mine, and my friends are closer to the top than a fresh no-name college graduate's.