That's a good question. I found this on Memory Alpha:
A desperate scramble among the creative staff ensued to trim as much as possible of the budget as possible; the entire prologue was (albeit painfully) scrapped, scenes were trimmed, all planned set construction for new starship interiors was abandoned (though a new Kronos One corridor set did get build ultimately), the planned live-action shoots in Alaska for the Rura Penthe scenes were scrapped as were plans for new studio models and other visual effects elements. Starship sets were to be entirely recycled from Star Trek: The Next Generation, which was concurrently in production, but was slated for its summer hiatus, when filming of The Undiscovered Country was planned to start, and only existing studio models were to be used.
I'm guessing this set was simply not built to hold up under feature film-level resolution.
Edit: elsewhere on the page, it says the galley was a redress of Troi's office.
The one that bumps me most is the Totally-Not-Ten-Forward Office of the Federation President.