Hats are in.
One could blame Kennedy not wearing a hat at his inauguration for the decline, or perhaps it was just a change in spending habits from the middle of the 20th century. But they're back now, mostly styles with a prominent brim. There is more to it than matters of taste though.
In an age of wearable computers - hats represent extra processors or a host of other features. Some collect solar energy, many contain further coils of antenna, and others have built in sound. These articles also present a good place to mount a flip-down screen to make the Sphere augmented reality system visible, rather than the normal reliance on bulky goggles.
Fashion hasn't gone entirely to 1950's style - though. It hasn't gone the way of space-clothes and jumpsuits like 50's Zeerust either. If anything, its a bit more 1980's counter-culture. Leather - real leather - has become far more expensive after caps were placed on herd sizes to limit industrial farming, so the punk look is something that flaunts wealth. On the other hand, the hacker eschews old T-shirts and jeans for something with a longer cut - if only because adding a jacket is a second processor and sleeves are convenient places to mount buttons for control.
"Stand alone" computers are still the mainstay. Small as processors have become, the stuff in clothes still has limited power, (both battery and processing), and tends to wear out quickly as movement frays the internal wiring. Furthermore, the sphere over-lay Head Up Displays are a lot more straining on the eyes than a real monitor. Although its possible to type with buttons mounted on a sleeve, or to dictate messages in a quiet setting - most people prefer to carry a small folding keyboard or use hap-tic feedback gloves and a Sphere image to work, or a "real computer".
Of course, modern machines rarely look like discrete boxes however. They're often integrated into furniture to take up less space, with screens and keyboards popping out of their recesses as necessary. Its dedicated gamers and hackers that use anything that looks like an old computer case - its easier to swap a new video-card when its a physical case, than to dissemble furniture to get to the integrated parts. Some have even complained that furniture designers have caught up to and surpassed the auto industry with planned obsolescence. How often did a couch need upgrading before the age of computers?
Post event, fashion has taken a more retro-look. Wearable computers were often rather stiff, and with the absence of most servers, there isn't much reason to use them - most of the file storage was outside the garments. Natural materials are easier to acquire and repair, and are often a bit more comfortable.
There are certain nano-integrated fabrics thar are abel to react to the weather with small jolts of current making tiny memory metal wires shift the poores to stop water ingress or puff up for warmth. A jacket like that may be worth killing for to some, but definitely a valuable possession or trade good for the rest.
*BBC video on the military use of wearable computers