You can't leave it on a cliffhanger like that. Why does he end up a driver? Or provide more details. This seems like an interesting story.
He had the means so he paid off his mortgage, invested in another property, took care of college fund.
Decided he didn't want to spend rest of his days wringing his mind and drenching off energy into deciding and debating whether it is ok to call a lambda from another lambda (yes I have seen this in production and the more experienced engineer decided to do it because he had been there longer and decided that's what he wanted to do... don't ask me which company was this but it was a FAANG) or setup a step function to orchestrate the two lambda calls... or some such equivalent problem he might have come across in his SGI days.. and instead picked a job that required little amount of cognitive effort compared to what he would have done if he was still in the same line of work but still managed to support the rest of his life/needs/responsibilities.
Might as well have been an artist, construction worker or he might as well have done nothing, absolutely nothing, and it could have been everything that one would have thought it could have been.
I won't judge knowing what I know at my age. People do what they do.
Feel free to imagine what you would imagine this ex-SGI engineer's life to have been and make it negative if you want it to be. No one knows until OP throws in more details if they have any.
https://www.harvardmagazine.com/2025/05/harvard-taxi-drivers...
Macguire's original study on taxi drivers:
https://pubmed.ncbi.nlm.nih.gov/10716738/
BTW it's Fall! So here's to memories - "Four Strong Winds" written by Ian Tyson, sung by Neil Young: