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?
Vogue tells a different history of the trench coat, claiming its origins are actually raincoats for active well-to-do British gentlemen:
https://www.vogue.fr/fashion/article/vogue-encyclopaedia-the-history-of-the-trench-coat
The “British Warm” was the intermediary as I understand it: a shorter greatcoat favoured by Britsh officers in WW1. The Trenchcoat itself was modeled to fit over, accompany or replace this.