Well, it is clear that Wilkinson has put a ton of thought and meaning into his costumes. As much as I am not a Snyder fan and have my reservations about this film, he sure knew how to pick his costume. Wilkinson is a brilliant. You can see it as much in Bruce and Clark's attire as you can in their superhero costumes.
Take Clark for instance. It is a perfect update of the classic mild-mannered reporter look. I think the more casual, hipster attire proposed by some for Clark isn't right for a Clark Kent who works at the Daily Planet. It's too informal for the sort of stuff they cover. Whereas everything we have seen of Clark from set photos to this new inside shot on the inside cover would fit in perfectly at say the Washington Herald on House of Card. It is modern business casual. You will also notice that Clark's attire is a bit relaxed in its fit, perfect for hiding his physique. On top of that, the colour palette and patterns are evocative of his rural upbringing. Wilkinson has him dressed in a lot of plaids and an earthy, autumn colour palette. Also, look at that brown car coat, or possibly an oversized sport jacket, Clark wears in the Gotham Police set photos. It looks like suede or ultra suede, which once again evokes his Midwestern, rural background. Clark's shirts also have button down collars, which is a distinctly casual, American style on a dress shirt.
In contrast, Affleck's Wayne is dressed in a very formal, but traditional manner. Much of his wardrobe is evocative of the 1940s-1960s and recalls the fashions of Batman's pulpy origins and also the great American titans of industry during its golden age. For instance, from what we have seen, Bruce wears a lot of jackets and suits with peak lapels, which were much more popular in the 1940s. He also typically wears a collar pin with his tie and dress shirt, which once again is a style more commonly associated with the 1940s. It also has the benefit of creating a similar collar profile to the button down collar, but with greater elegance and sophistication. Bruce also seems to dress in Batman's traditional colours of black, grey, and blue. This Bruce also chooses heavier fabrics for its tailored clothing. His jacket in the taunting note shot appears to be tweed or flannel with a mottled appearance. The heavier fabric is once again evocative of the earlier part of the 20th century when men wore heavier suits due to a lack of central heating. Also the heavier, softer appearance of the materials has a certain rustic, luxuriousness to it, befitting of an old money billionaire. Michael Corleone wears a lot of similar fabrics in The Godfather Part II as does Don Draper in the later seasons of Mad Men. In the Metropolis scene, Bruce wears brown wingtips with his navy three-piece suit. Brown in the city with a business suit would traditionally have been considered unusual in Europe. It is very much an American look. Wingtips are an informal style of shoe, typically worn in the country. As such, they had a certain American informality to style. However, the craftsmanship of the brogue detailing on the shoes once again show a certain wealth and luxury.
All in all, Wilkinson has done a phenomenal job with the wardrobes of our two main heroes' secret identities.
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What comes in fashion, goes out of fashion. Fine men's tailored garments are constructed to last for a decade and therefore it is inadvisable for a gentleman to adhere too strictly to what it is in fashion for it will be out of fashion in a year. Also, really fashionable attire dates very quickly and is a bad choice for film costuming (which is why everyone laughs at Roger Moore's bell bottom tuxedos and safari suits from the 70s Bond movies).
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