To me, the biggest cost difference in the past 20 years is increased difficulty of getting an upgrade with miles. It may not literally be a fare difference, but it translates directly to either paying more money or flying in a lower class of service. Fortunately, trans-oceanic business class seating today (lie-flat beds and such) is roughly on a par with what F was 20 years ago, so in that sense it's a wash. The meals aren't as good, but F meals aren't what they once were either - and anyone who flies in front for the meals hasn't spent much time in good earth-bound restaurants.