I am an older programmer, and what you described is my career, more or less. And I fight off recruiters with a stick, switch jobs every year, and laugh at the articles about how there's ageism in the industry.
The problem I typically see isn't that someone focused on a technology for too long and became unemployable. It's that they focused on an employer for too long and became unemployable. I started my career doing C and sql 20+ years ago. I could still easily make a living at them if I wanted. My second major technology was enterprise Java. I could still make a living at that if I wanted (and to an extent, I still do).
But people spent 10-20 years in a culture. They don't know how to even look for a job anymore. Their skills may be great, but they've never put in a job application online. They're unknown to the recruiters. They don't know how to write a good resume that reflects their abilities. I watched my wife go through it last year. Laid off after 15 years at one company, her problems were twofold. First, she had narrow but deep domain expertise. Second, she was rusty at job hunting and out of touch with industry standards that had evolved without her. She still believed in waterfall and thought agile was a joke - not good for someone looking for product owner roles! She learned, but it took a while.
The problem I typically see isn't that someone focused on a technology for too long and became unemployable. It's that they focused on an employer for too long and became unemployable. I started my career doing C and sql 20+ years ago. I could still easily make a living at them if I wanted. My second major technology was enterprise Java. I could still make a living at that if I wanted (and to an extent, I still do).
But people spent 10-20 years in a culture. They don't know how to even look for a job anymore. Their skills may be great, but they've never put in a job application online. They're unknown to the recruiters. They don't know how to write a good resume that reflects their abilities. I watched my wife go through it last year. Laid off after 15 years at one company, her problems were twofold. First, she had narrow but deep domain expertise. Second, she was rusty at job hunting and out of touch with industry standards that had evolved without her. She still believed in waterfall and thought agile was a joke - not good for someone looking for product owner roles! She learned, but it took a while.