I question the statistical validity of your data, but more important I question why you think such a pax is traveling light.

I am of the same nature. Not a duffel, but a backpack of decent size. I can carry more with me if need be than via a rollar, and certainly more "bin friendly". And have no issue with the carry-on police.

There is a significant penalty paid for the inconvenience of lugging around that wheeled thing.