This.

I see two things happening here: (1) American spending less on clothing and (2) Americans having less self-pride in their attire and presentation.

I've spent a fair amount of time in Latin American countries, and a real sure-fire way to identify tourists is to look for people poorly-dressed or those who look like they just don't care about how they look.

E.g., despite much of Mexico being quite hot, you will almost never see a local Mexican wearing shorts, even on beaches. Tee-shirts maybe but almost always a freshly-washed button-up shirt. (Or a swimsuit if they're swimming obviously.) This is true of other Latin countries too in my travels. It's really humbling to see.