Some people struggle with reinvention. I tend to branch out every 4-5 years. I think this person thought he had the one true career and had difficulty with reality.
Our high school cohort was just old enough to see the end of the “dinosaur” tech company era. This guy was a few years older than me (his younger brother was my age), I think he thought he was retiring with a gold watch or whatever.
It seems quaint now, but it was a thing. My dad’s friend was a GE lifer, they moved around the world like they were in the army to the next posting.
Today, we’re all more paranoid and mercenary, even govenrment workers jump ship.