I understand that modern outer layers are more functional. A leather jacket, for example, can be dressed up or down so as to be worn in a variety of situations. It is also better at keeping you warm.
However, I think capes/cloaks are more aesthetically pleasing garments. It also feels good to have the fabric flowing around you as you walk. But what do you think?
It’s because of cars and trains
Horses and to a lesser extent bikes let you just throw the cape out behind you as you ride, but if you’re riding in a chair, you have to bunch it up as you’re getting in so you don’t accidentally auto-asphyxiate yourself with the titanic cheeks you inherited from yo mama
100% of the cloaks and capes I’ve seen IRL have been as part of either someone’s weird cosplay or some neckbeard/weeb shit. I think that, a bit like the fedora, they’re just sorta ruined now due to the people who wear them.