While I agree with you that most consumer tech is getting smaller, I don't know if that trend applies to statement products. Or, at least, products whose performance makes a statement.
Judging from the driver size, these are as big as they need to be. Any smaller and they would have had to use a smaller driver, which would impact the astonishing FR they have. That's not a great compromise, IMO.
If you want small and great sound, there are always products like the UE11 pro. For the rest of us, who have little intention of wearing $1400 out on the street, the size really isn't an issue. I never see myself wearing them, anyways.