The great advantage for a bodycam is to the wearer. For the wearer knows that they can stay calm whilst the other person incriminates themselves.
I worked in voice based telecommunications for many years and there was a job I did in my very early days, some 35 years ago, that shows the benefit. We were a company that often received bomb threats and other verbal assults. On one occaision, a woman was berating me for not helping and not doing my job. As soon as she had started, I hit the RECORD button and sat back, speaking quietly and politely.
Later that day I got called to HR (as I had expected the woman would demand it) and took the tape with me. After they listened to the woman screaming (and I mean screaming) at me and that I had done all I could to help her - I was congratulated on being a good member of staff.
Cabin crew might like to think of the benefits of keeping their job.
NOW, the other side of the problem is management demanding ludicrous turnaround times that can upset the staff as much as the pax. But no body cam can tell the Board of Directors about that - because the shareholders come first.