The issue here is that skeuomorphic UIs are commonly mistaken for "realist" UIs. Any application that resembles a calendar, whether it has fake leather stitching or not, is a skeuomorph. Any presentation software that creates slides that look like old 35mm projection slides, is a skeuomorph. A trash bin is a skeuomorph. A word processor that emulates a sheet of paper, with margins, is a skeuomorph. Any application that emulates an address book is a skeuomorph, even if it doesn't look like a real book. Its functionality is still skeuomorphic.
Flat design does not change skeumorphism; it merely reduces the textures used to their bare essence. It's impossible to do away with skeuomorphism completely, because many of the things we actually do on our machines correlate with things we do in reality.
And whoever proposes such a change is grossly out of touch with reality.
Personally, while I think ornamentation like how the old OS X Aqua UIs looked and Windows 7's Aero, is dated and clunky, the newer interfaces of OS X and Windows 8 desktop mode actually reach a fair point between flat and ornamental, bar the awful Address Book, Game Center, Notes, Reminders, and Calendar in OS X. It's folly to reduce everything to completely flat; it's a usability nightmare and I've seen power users struggle with some flat web designs on a tablet.
The solution is to keep light gradients, light drop shadows, and some gloss. Just enough to keep a good level of usability, while not adding excessive ornamentation.
The current Flat UI designs are just designer laziness. Just take a look at Google's marvelous implementation. We can do better.
Much better.