Something that seems like it's become a bit of a lost art, is playing a fully single player game with a friend. It might be 90% just one person playing and the other watching, but it can still be a fun shared experience. I think, and I might be mistaken as I'm a big shut-in, but I think a lot of people just don't consider this and gravitate towards more intentionally multiplayer games.
Or they watch someone play on twitch. That's fine too. I like doing it in person when I can.