it's difficult to pick between all my favorite videogames like this, but the question posited provides an interesting conundrum for me. the wording of "everyone here should play", meaning it should be at minimum, accessible, but also considerate? i guess this is imparting my own conditions on the question, aiming to find something that anyone here(on this website) could play.
i gotta go with Starcraft 2 as one recommendation for something more complex. it's free, it runs on toasters, and at lowest difficulty is perfectly playable for nearly anyone. the free campaign you get is Wings of Liberty, which has a simple yet elegant storyline. it is decently lengthy, each mission is around half hour or so, with 30 ish missions to play through. some are optional, of course, and some are only playable on a second playthrough with different options, so there's replayability. since it's an RTS(Real Time Strategy), it also has plenty of depth for any wishing to play on higher difficulties or step into the multiplayer.
as for my second recommendation, Cyber Hook is my next one, for something more simplistic. it's cheap(like two bucks when on sale), it runs on toasters, and doesn't demand much of the player. you can cruise through with longer times, going through a relaxing vaporwave fly through. if you're looking for challenge, you can go for really fast times on courses and get a lot of depth out of the game. it's simple and digestible, with hardly any story to speak of. it is short, however, with maybe 6-8 hours of playtime. that doesn't take into account the custom made community courses, or replaying various courses to set faster times.
i think both of these are pretty accessible and easy to pick up and play for nearly anyone. i've had a thoroughly enjoyable time with both.