The 1980's were, just like in many other countries, the Golden Age of roleplaying as a hobby in Sweden. The first roleplayers that I know of (some are personal friends) began playing in 1976, using Dungeons & Dragons rulebooks imported from the US. As the hobby slowly grew, other games, like Runequest, Call of Cthulhu and Traveller, were added. The first major breakthrough for the hobby came in 1982, when the first Swedish RPG arrived: Drakar och Demoner (basically a translation of Chaosium's Basic Roleplaying fleshed out). It became a hit, selling more than 100,000 copies (in different editions) between 1982 and 1992, this in a country which had some 8 million people back then. Other games followed from the same publisher (Äventyrsspel), like Mutant (1984), Chock (translation of Chill, 1985), Sagan om Ringen (transl. Middle-Earth Roleplaying, 1986), Stjärnornas Krig, (transl. Star Wars, 1988), and the infamous horror RPG Kult (1991). Another publisher of Swedish-language RPGs was Lancelot Games, with Western (1989), Khelataar (1989), and Wastelands (1990). At the same time, stores popped up, offering a wide selection of English-language games.
So, this means that the player characters can enjoy roleplaying games just like the kids in Stranger Things, and wouldn't it be really meta to have the characters playing Mutant while strange things happen close to the Loop?