[switch_bro]

A few points come to mind. Are the 50 yo people really computer programmers, or are they managers / architects / scientists / etc?

The point is not that there is nothing to learn, but that after 8 - 10 years, additional learning/experience does not give you a competitive advantage compared to younger programmers.

Finally, you can always have exceptions, niches, etc. That does not change the dynamic for the field as a whole.

[Retric]

I know several older programmers 55+ who run rings around younger programms. They don't just write better code they also pick up new systems, languages, and techniques faster.

I suspect part of this simple selection bias where the best stick with programming for longer periods, but there is huge bennifits to really wide ranging backgrounds. Sure, many things become outdated, but the 4th time you see the same idea presented in a new way your just picking up syntax not a new way to think.