I haven’t met anyone who plays Realm in many years. I think the most common genre for me to find someone else doing was the .io game suite, but those are both free and easily accessible for most. The less common instances are whenever I find someone who grew up with a certain SNES game, or the system at all, for that matter! I think there’s been 6 instances, and 2 of them were relatively new to it all. Guiding them though DKC and ALttP was fun! Otherwise, many of the games I do sold well, and lots of people at least know of them.
Edit: I do remember three specific surprises, actually. One was an acquaintance of mine that somehow knew both of Starfleet Command (Orion Pirates addition, even!) and the 1979 Ultima franchise, including the fan remake of Ultima V: Lazarus Edition!
Another surprise was someone who was not only familiar with Quest for Glory: “So you want to be a hero?”, but many of the old games Sierra created! I managed to surprise him about the existence of Pizza Elemental in the second game. x)
Finally, the third one only kind of counts, dive is not me specifically, but my dad does this game called “Elite: Dangerous,” and I discovered that one of his friends also played it, so his friend (because I worked with him then frequently) wanted me to request that they hook up online sometime. It was hilarious to hear him geek off about that on our car ride