This is how men manage to carry on exploiting and objectifying us.
I'm not sure if it's naivety or just that there's a load of the usual MN posters who like to have a go, all chiming in, but all this "you have to be a certain weight for safety" stuff is nonsense. It's an excuse that allows misogynist men to continue to recruit pretty female flight attendants to sell us as sex objects for the male gaze.
The history of female flight attendants is that airlines used them as sex objects to sell the flight, designing skimpy outfits, employing slim and attractive young women and marketing them as if they were sexually available to male passengers.
Here's an article about this. librarypartnerspress.pressbooks.pub/gendersexuality3e/chapter/sexism-takes-flight/
Sure, that was a long time ago, but this is in the roots of the profession and these kinds of sexist attitudes persist with many management - often older men, and also passengers.
In countries where they are allowed to get away with it, airlines do still advertise for beauty standards.
Here's an Air India ad from just a couple of years ago:
Maximum age limit as on 01.07.2019 shall be 27 years
Marital Status: Unmarried
Height / BMI: Minimum required for female:157.5 cms (5’2”) /BMI – 18 – 22
Cosmetic Appearance: Should be well groomed with Clear complexion without any noticeable blemish, no odd scars /birthmarks. Even and regular teeth.
feminisminindia.com/2019/07/22/sexism-female-flight-attendants-await-feminist-revolution/
The only reason airlines don't advertise so blatantly for sexist beauty standards in the UK is they're not allowed to by law - so using weight as a safety issue is their way of getting round it. Don't fall for it!
If they were so blimming concerned about safety, why are female flight attendants put in pencil skirts and heels? If safety was the genuine concern, flight attendants in flats and clothes they can easily move in would be prioritised over appearance.
This issue is covered in this article: www.bbc.com/worklife/article/20180219-what-dress-codes-really-mean-for-cabin-crew
Several of the women BBC Capital spoke with who had worked for a number of airlines and described sexism on a daily basis which they felt could be attributed to the enforced dress code and image: everything from barbed comments about their intelligence to sometimes feeling physically threatened by passengers.
Stop being so bloody naïve, people! The OP has it right, the airlines are sexist and her friend isn't paranoid to feel she's being objectified.