There could be another factor here, where fashion is how people signal their alignment to perceptions of power. Beau Brummel's relative minimalism was taken fro

There could be another factor here, where fashion is how people signal their alignment to perceptions of power. Beau Brummel's relative minimalism was taken from standard riding kit at the time, just without the flourish of cavalry. The style lives on today in the form of the shadbelly[0] worn in competition in dressage. Given it was toned down military dress, it was literally the tactical cavalry wear of the time. The analogy or equivalent to Brummel's style today would be something closer to a luxury brand with technical cred from their tactical lines like Arc'teryx, Prada, Beretta's clothing line, and perhaps Fjallraven. I have an opinion about this because I looked at a business re-designing men's riding clothing, as over a couple decades I found the now-unisex attire discourages men from riding horses in any non-western disciplines. I gave up the idea because I could just buy clothes from some of those makers above and ride in them instead. The silhouette looks a lot more more "Horse Soldiers," than "Downton Abbey," but building a new retail brand for a market I was inventing wasn't a startup play. But that's what I was able to interpret about menswear along the way. [0] https://en.wikipedia.org/wiki/Shadbelly https://en.wikipedia.org/wiki/Shadbelly