3) Marvel Trusts Its Audience
In the early days of superhero movies, filmmakers had to really hold our hands when introducing new characters. Each and every hero required a whole movie dedicated to their backstory to the point that when Sony rebooted Spider-Man, it was apparently necessary to retell the entire tale just in case there was anyone left on Earth who doesn’t know how Peter Parker gains spider powers.
At this point in the MCU, though, Marvel has faith that its audience can follow along as protagonists are thrust upon them without elaborate setups. In Civil War, two major Avengers are introduced, yet the Russos understand that viewers are smart enough to pick up on who these people are without lengthy origin stories.
With Spider-Man, we don’t need a slow motion sequence depicting the death of Uncle Ben for the umpteenth time. Hell, the name Uncle Ben is never even mentioned. The Russos operate under the assumption that we all know who Spider-Man is, and the result is an impressively economical character debut. With a lesser-known hero like Black Panther, in mere minutes, Civil War communicates everything we need to know about him through the actions he takes rather than through exposition.
Marvel has actually been doing this for a few movies now. Scarlet Witch and Vision, for example, are now crucial to the series’ events. Both of them were unheard of until Avengers: Age of Ultron, and the latter character only showed up in the final act of that film, yet we as an audience get who they are without hours of screen time.
When it comes to Civil War, it is just assumed that you saw Age of Ultron, or if not, you can figure out through context what Wanda’s role is. Even the first Avengers provided some brief lines to recap previous installments, but Marvel is done with the hand-holding, and Phase 3 will be better for it.