You are calling out the Fashion Industry. And fast fashion is a blight and should be a crime. But that's not what I'm talking about. People have been making themselves pretty for at least 30,000 years, both with body art and clothing. One person long ago added decoration to a utilitarian garment and pretty soon everyone's doing it. All subcultures have a fashion aesthetic of their own. American gun culture has that dopey faux military look. An all black rodeo has a different fashion aesthetic than mostly white rodeos. If you think a t-shirt and jeans (or sweatpants or cargo shorts) is not a fashion choice than you're fooling yourself. You are making a statement about who you are.
I can't wear couture fashion. I wouldn't be able to afford it even if I could. But I admire the art, craft and skill that goes into creating it. Just as I admire the art, craft and skill that goes into designing costumes for shows like SNW. I would not want to live in a world (or future) where we couldn't express ourselves through clothing and body decoration, where we all had to wear the same outfit, the same color, the same hairstyle as everyone else. (I wouldn't want to live on Vulcan in the TNG era for instance.)That sounds horrible to me. And very very boring.