What does your dad work on exactly? When did he start programming?
I hope I'm able to age so well; I'd love to get a law / medical degree at 65 and start a whole new career in my 70s :)
Today he's responsible for reporting the hell out of a telecom's database (Oracle DB for the most part) in a large IT department. He's an "expert", not a manager nor team leader. He does a lot of SQL wrapped in Java spit out by Tomcat (iirc) and uses a deeply customized Eclipse editor. He's also created several logistics sw on the side through out the years, launching a couple of startups in the 80s and 90s, mostly for automating shipping and manufacturing processes, and that's how he paid for my college degree in CS.
I remember when he bought one of the first IBM RISC 6000 computers ever in 1990 (he was even featured in an IBM paid ad-article), loaded with AIX (IBM's Unix flavor). I wanted to help him out setting it up or just hack on it, I logged into the console and I asked "how do you edit a file in this thing?" (I was doing PC and DOS back then). He came over and said "I think it's called `vi`". He keyed in `e` or `i` and said "there, now type ESC + :wq to save the file". It blew my mind. I was 15.
My grandparents keep mentally active (they are in their 80s) and pre-covid socially active. Plenty of books to read and things to learn, but they do so purely for fun.
Why not just learn things for fun at that age?
What I fear is traditional retirement that I've seen some people choose: spending the rest of their days watching TV and grumbling about 'kids these days' :)