That's because most Americans (obviously not all) have gotten past the phase of "showing off" their wealth with clothes.
He didn't start a trend. Most American's simply dress casually. We are a casual nation.
A non-American commenting on it:
Style - Bangs & a Bun - Fashion & Lifestyle Blog | www.bangsandabun.com
"One of the most popular posts I’ve written on this site was one I did a couple of years ago about how
Europeans dress better than Americans. It seems to be something people Google a lot: ‘why do Europeans dress better than Americans?’ Or ‘Americans dress lazy’ or other such terms often lead to that blog post and it still gets people leaving comments on it. It’s a weird topic. The comments section is filled with smug Europeans or angry Americans talking about how judgmental I am or how Europeans are either gay or have really poor hygiene, which has nothing to do with anything. Admittedly, the style in which I wrote that post was pretty harsh, but has my viewpoint changed? Do I still believe Europeans dress better than Americans?
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A couple of years on from that original post, I’m not sure it’s as black and white as it once was. I’d say in broad strokes, yes, the original points I made in that post still ring true; North American fashion is all about ‘casual comfort’, they lack good tailoring and it seems most people aren’t concerned so much with what styles and fit actually suit them, as much as they are with convenience.
Interestingly, in the original post I wrote on this, the American commenters seemed to take a stance of how vain it was of me to even bring this up, how no one really cares what they wear and it doesn’t matter. That remains a complete non-argument to me and a downright ridiculous thing to say. You care, everybody cares about how they look. What you wear, how you choose to present yourself is part of an artistic expression of who you are – it matters. I understand not everyone is going to keep up with trends, but saying you don’t care is not realistic and quite simply, not true. And if you don’t, you should – you should absolutely take some pride, time and consideration about how you put yourself together. That’s nothing to be ashamed of.
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Most Americans look at the tags of clothes and say "Dry clean only...bah! forget it"..or "hmm...this is wrinkle free...awesome!".