The culture bit is the most important. You could add 100x the current headcount at all American airports and because the workers simply don't give a shit about doing good work, because they're treating it as a 9 to 5, where they have to go and suffer through a meaningless 8 hours, or worse, they treat it like their own personal access to other people's stuff to loot at will.

The TSA is security theater, a vast majority of American jobs seem to be competence theater. You only ever tend to see care and craft in small business and actual crafts. It's so rare that it's incredibly refreshing to find anyone in any business that bothers to do good work and take care of the small things.

It's not about respecting the baggage handlers. It's about a culture where you respect yourself such that you are obliged to do the best work you can, whether it's baggage handling, being a CEO, or flipping burgers. Self respect and respect for the job far outweigh any notion of employers or other citizens respecting baggage handlers. They have sophisticated notions of status and face and place in society that are sadly absent in American culture.

You could take the Kansai airport baggage handler team and drop them into any airline in the world, and they'd perform to the same high standard. Take any halfass United Airline baggage team and drop them at Kansai and they'd be breaking guitars, killing dogs, and all the other usual shenanigans just like back at home, and they wouldn't give a flying rat's behind about how their employer respects them or not. They're there for paychecks. Respect doesn't even enter into consideration.