I mostly flew Pan Am internationally in the 80s when the experience was far removed from the early 70s when it was the charter customer for the 747 and the entire hump behind the cockpit was an upper deck lounge.
The A380, in particular, is allowing airlines to bring some of that glory back and actually use technology to improve the experience
Suites on Singapore Air
Showers on Emirates
The extended hump on the 747-400 shared by just 8 passengers on Lufthansa, each with a bed and a seat
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