It's a bit early for these comments. There aren't that many programmers in their 50s because there wasn't as much need for programmers in their twenties, 30 years ago. Demand for doctors has been more steady.
That's half the story, but it's a big part of it.
The other half is that it's an area with gradual drift out & little drift in.
That half needs some explaining but it seems like more of a young man's game then it is. It's easy to get behind. If you're out for 2 years, it's daunting to get back in. The opposite is true for some domain (like medicine). You get very little drift in to the field (more programmers become HR people or sales people then the other way around). It's a first career, not a second.
It depends. You could be out of Unix or C or Oracle for 2 years and come back. It's only "front-end" technologies like Flash, Rails, PHP, AJAX that suffer from the rapid churn and the latest thing when you come back didn't even exist when you left.
That's half the story, but it's a big part of it.
The other half is that it's an area with gradual drift out & little drift in.
That half needs some explaining but it seems like more of a young man's game then it is. It's easy to get behind. If you're out for 2 years, it's daunting to get back in. The opposite is true for some domain (like medicine). You get very little drift in to the field (more programmers become HR people or sales people then the other way around). It's a first career, not a second.