Between 1900 and 1950, only about 10% of Americans were nonwhite. Today 33% are nonwhite, and the United States is about 15% blue-eyed.
In the '70s and '80s the fashion models who exemplified the All-American look were typically Scandinavian. The look advertisers want today favors honey-colored skin, brown hair, and green or brown eyes. The most successful models are coming from Brazil.
But even as blue eyes give way to brown, lighter eyes will maintain a certain allure. When people see something pleasurable, their eyes dilate, which is considered attractive. Since dilated pupils are easier to see on lighter eyes, they have a natural appeal.