One aspect that is definitely better today is the seats in Business/First. I flew Heathrow/Seattle in 1990 on BA Business class and the seats were horrid - little better than coach. Today's business class seats are fantastic almost regardless of the airline.
Cabin service has gone down hill though. I got bumped to First on Pan Am going Seattle/London back then and it was a full seven course dinner - including made to order green salads, caviar, and if you ordered prime rib for the main course they brought the beef out on a trolley and you pointed to the cut of meat you wanted and they cut it to order
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