Any kind of game
EDIT: changed from suggested to mentioned and made the title more clear
Not every person has seen every game being recommended or just mentioned on the internet. But they’ve likely seen every game, they played themselves, on the internet, except for pre-internet or analog games that they never looked up somehow.
If that’s what you’re looking for, that is an interesting question, but I’d assume that most answers here are just as incorrect as this one.