I've flown IAD-ICN several times and would guess that maybe 80+% are of Asian ancestry although many live or were born in the US, but I would guess that on most transpacific flights of other airlines the ridership is predominantly Asian. Can't say it makes the flight any more exotic since Asian passengers do what non-Asian passengers do - sleep, read, and watch movies. Announcements are made in Korean and English and there is usually a Korean offering at the mealtimes. Korean Air provides good service at a good price and Incheon is a great airport. You made a good choice of airline.