I'm almost a boomer. I started out in a Big Iron shop that mainly ran Cobol I haven't touched it in decades, and I was an Admin, so I barely touched the stuff. Now I could read the stuff, but not code a hello world.
A few years back a friend my age, who was a CS major, but had mainly been a mom for 2 decades returned to the job market, thinking that she faced an impossible task, that she had obsoleted herself. She was working within a week, maintaining Cobol at a bank, and making mint.