I know someone up there in years that enjoyed the Far Cry series. Didn’t really expect that. shrug
More generally I think it’ll commonly be something that relates to their interests when they were younger. Someone that retired 20 years ago from aerospace engineering might actually really enjoy Kerbal Space Program or even Outer Wilds, a former industrial foreman might like Factorio, for a retired military historian, bring on that Total War.
I can see games like Big Game Hunter and Truck Simulator being more broadly popular with certain segments. Some sports games maybe, like a tennis game or some golf thing maybe, I don’t know much about those. A simpler, realism-leaning racing game maybe. Flight simulator works great here.
The main thing is I’d avoid games with lots of layers of game design and abstraction. It should do what it says on the tin, and there shouldn’t be many steps or abstract mechanics between them and getting into the meat of the game and the core gameplay loop.
Minimal menus is probably a good idea. Like, a Paradox Interactive game would probably be a poor choice, just because they have so much you need to learn to become a proficient player. Fine text can be hard to read too, so menus and tooltips and complex status interfaces are usually gonna be pretty meh for most people. Can’t play Starcraft if you have to squint and lean in every time you want to know how many minerals you have.
Want that learning curve to just get into the initial gameplay to be pretty gentle overall. The experience should be fairly intuitive to real life, and real life doesn’t have that many menus and buttons. Usually, depending on their former career I guess.
Kudos for doing this btw.
(oh, and sorry I couldn’t answer your core question)