It's hyped up in the U.S. because they're not readily available in the U.S. $90K is the MotoRex price because they had to foot the R&D bill for the conversion procedures. If Nissan had sold in the U.S. market, the price for a GT-R would have been way lower, because Nissan could have spread the costs across the entire sales batch. Surely it would have been enough to push the price of a new GT-R in the U.S. under $60K, perhaps under $50K, making it much more reasonable.
Personally, I think Nissan could have sold quite a few in the U.S. over the last 13 years, but apparently, they didn't think so...