Yes, it has declined IME, at least relative to the price. It used to be easy to find a nice silk blouse or skirt at a moderate price. Now the blouses are either
rayon or they are a
stiff and papery silk. Or J. Crew will slap a "collection" label on it and charge
$300. I understand that prices are bound to go up, but that huge increase is not warranted.
They have stopped lining some of their pants, even suiting pants. They use inferior fibers for some of their sweaters--the dream yarn in particular has been a problem. The cashmere is also low quality (although I don't know if it was ever very good--the cashmere I bought there 10 years ago was also lousy).
I do like their merino and cotton. The shoes also seem to be well-made for the price (especially if you buy them marked down).