Think all you want. You call them that and they will probably give you shitty service. They are brain washed that their primary function is safety (plane evac, etc.) and serving stuff is secondary. While technically true, we all know in reality it ends up being 95% service and 5% safety. But on those rare occasions when an evac does happen, they always seem to make it work.....I think "Steward" and "Stewardess" are totally acceptable... the dictionary definition certainly agrees: "steward
1 a person who looks after the passengers on a ship, aircraft, or train and brings them meals."
Same holds for "Stewardess."
They can be real ass pains but the FAs do serve a critical safety purpose and are needed. Flight Attendant describes their function a lot better than Stewardess or Steward. I can't really blame they for not wanting to be called "Stew". This is not so much of a PC thing, but is more of a reflection of how their job functions and scope have changed since the days of the DC-3.