Every now and then, I venture out to go shopping at mainstream chain clothing stores. Although I find it onerous, there are certain things I can't get at thrift stores. For example, I can never find nice jeans.
The last time I set foot in these stores was about two years ago. It was tough to find pants my size at that time-- many stores simply didn't sell pants with a 30 inch waist. This year, it was even harder, since some of the stores that formerly carried 30W pants no longer did. I managed to find my usual 30W 30L size in two stores, but I had a bizarre experience in both cases. I put them on, and they were falling off my waist. Since my waist size hasn't changed in two years, and my old 30W 30L pants of the same brand still fit the same as they did when I bought them two years ago, I have to conclude that both stores have changed their definition of "30 inches". My new size is 28W 30L, which is tough to find these days.
I know women's clothing has been doing this for a long time, but the difference is that men's clothing is ostensibly sized in inches, an actual objective unit, rather than an arbitrary number like women's clothing.
I have naturally thin hips, but they aren't abnormally thin. I have no trouble finding pants that fit in France for example. In the US, leanness is no longer normal in the statistical sense. Clothing companies are adapting to this new reality.