It use to be hard to do computing - you had to understand compilers and assembler and you were often on your own. Now I'd say that anyone who can do Sudoku can understand many common algorithms. Here's a simple example (https://blogs.ch.cam.ac.uk/pmr/2014/03/15/segmentation-of-im... Ramer-Douglas-Peucker segmentation of contours). I've illustrated it with kangaroos - but I think children of (I guess) six years old could easily manage it. And so could a 75-year old.
The thing that's different is the frameworks. 10 years ago you'd have to build this from the bottom up. Things like reading images (Java.IOImage is not cuddly). But now we have boofcv.org and Apache (and similar in Python).
Learn to use libraries and you can be an effective programmer. The skill is finding out what's out there. And here the social skills are important. Go to hack days - we had a wonderful NHS hack day in Cambridge. Find your makerspaces. Contact Mozilla, Wikipedia or OKFN. They'll all love to hear from you.
Do you like crosswords? You've got half the skills required for natural Language Programming already. And remember there are people to help you. I will.
And thats' a great idea - an over-70s hack day. If you are interested, tweet me @petermurrayrust Not on twitter? That's the first thing you should think about!