Your points about attractiveness/youth v ability/experience are correct. However, the survey wasn't about the most attractive Cabin Crew. And attractiveness and ability aren't inconsistent.
This was a survey of customer opinion, not people in the business. My comments were made from a customer's point of view about a customer satisfaction survey.
Why are you all so surprised that people take this kind of survey seriously? There are various tourist and hotel guides which sell millions of copies every year. Some use their own researchers, others rely upon customer comments. The guides take into account not only the quality of the food/comfort of the bedroom, but the quality of service given by the staff, e.g. efficiency, attentiveness, friendliness, courtesy, enthusiasm, attitude to customers etc etc. They don't deal with the safety of the establishment, the ability of the staff to evacuate the building in the event of a fire, compliance with food hygiene regulations etc, but they're still useful guides.
Don’t shoot the messenger; act on the message!