The difference: Context
Starcraft multiplayer is a Game of Sport, where character and story are nonexistent and mechanics/"interaction" are all that matters in a game of chess completely removed from any context other than the tournament you are playing in.
Switch over to campaign mode and the context becomes the story line and plot. Sure, the game still relies on mechanics but you advance through different scenarios where you meet new characters, form alliances, explore new worlds, and even switch sides and play as a different race based on the plot of the story. Solo play is a Game of Immersion.
The Dark Souls franchise has a good balance of the two. You advance across the world (semi) linearly in a movie-like fashion, learning about the various NPCs and lore of the world. You are also regularly invaded by other players, and then the game becomes completely mechanics/interaction-based until one of you wins the duel.
You're basically arguing that video games are/should be more like a football game than a movie. They can span both forms of entertainment, and people will choose to engage with one or the other based on personal preferences.