It's hard to separate purely audiovisual appreciation from the overall aesthetic, including the emotional impact. Overall, I would have to say Disco Elysium: the themes paired with the art style, 10/10 VO work (esp. in The Final Cut version), and 100/10 OST by Sea Power. They all come together to create so many human moments, across the spectra of possible life experiences.
If I don't have to discount nostalgia factor, it's got to be Doom (1993). Every line and stroke of that game is etched into my mental happy place.
If I do have to discount nostalgia, and focus in on audiovisuals alone (impossible imho, but we try), then it's Journey.