Fancy watches and Birkins are primarily fashion pieces. The ability to tell the time and carry stuff is incidental, and they don't do that any better than a Casio and a plastic shopping bag. That's why they can be priced as they are, and people will pay good money for them.
The issue here is that a smartphone's primary purpose is to do stuff on, Apple or otherwise. The fashion bit of it is secondary - the cachet of holding an iPhone is not enough to sell the things anymore (at least not at the prices they're asking). Until Apple invent an iPhone that makes the tea in the morning, they'll have to get real about prices.