What would be the cultural impact if the major Hollywood studios simply did shared cinematic universes from the start? I'm referring to the concept that has been done most successfully by the twenty and counting Marvel Studios movies. In this timeline it would just be assumed that when a studio produced a movie, it would take place in same world as the other movies produced by that studios, and movies would have cross-overs from the start.
Note the the Marvel movies are not all produced by the same studio, but in this world the cinematic universes would be studio driven, since studios were most integrated and at the height of their power in the 1930s.