Hmmmm.... I think this would be difficult to get passed.
A woman 5’ 3” 130 lbs, 1x 40 lbs bag
A man 6’ 3” 250 lbs, 1x 40 lbs bag
The man is going to be additionally dinged (120 lbs x distace) just due to he being born genetically tall and muscled?
Maybe if they set an upper max limit, and beyond that additional fee. Say, beyond 300 lbs total? 350???
I just see it as being headache material for the airlines and a bevy of lawsuits. (We Americans, we love our lawsuits.)
The man already get dinged every time he drives his car. light people get better gas mileage than heavy people.