To quote myself from the comment you replied to:

"Again, it is not about weight, it is about fitness level. If you are 180 lbs. @ 45% body fat you're going to have a hard time getting yourself down the aisle, let alone anyone else. 180 lbs. @30% body fat is a totally different story. That is for a woman. Take off 8-10% for a man. Women need and thus hold more fat naturally than men do."

FAT does NOT equal HEAVY.

https://www.verywellhealth.com/body-fat-percentage-chart-8550202

There is a HUGE difference between 180 lbs. and 45% body fat and 180 lbs. and 30% body fat. To be precise 180 x 15% = 27 lbs. - of fat. i.e. "dead weight" that the person has to carry around.

Pick up a 25lb dumbbell, or if you have access to one, a 25 (or 27) lb. weight vest. Put that on and do 10-15 minutes of common flight attendant-like activities such as squatting and emptying a dishwasher, bending at the waist and reaching around things, etc. You'll be winded quite quickly.

Keep that weight vest on: Now get your heart rate up to 180 like you'd have in an emergency and THEN start trying to lift and support other people. You'll manage a few and then you're done. That is the difference of 30% or 45% body fat at 180 lbs. of body weight.

You are comparing apples and oranges with your anecdotal examples. The women (and I know a lot in the professional gym where I work out) who weigh around 180 lbs. They do a lot of sports are NOT carrying 45% body fat. They are in the 30% (and often less) range. They are fit AF! I'd guess like the women that you know, and yourself.

This is also not about gender. A fat male flight attendant will have the exact same issue as a fat female flight attendant. Again, FAT does NOT equal HEAVY.