it’s what they claim. Watch
https://www.youtube.com/watch?v=mrCD-Sfs4fI and go to the 1h59m15s mark for the discussion on such safety devices. They conclude lifejackets are pretty much just for reassurance, so the same in all likeliness as the peanut policy. But would you get on a ship without lifeboats? maybe they are the same thing too
we’re obviously going somewhat off topic but I’d be surprised if flotation devices in general didn’t at least contribute to the limited survival of Air Florida 90, for example. Was the life jacket the one and only thing that saved lives there? Probably not. Would more life jackets have saved more lives? Probably not. But for a quiz show to claim they’ve never saved a single life seems incorrect. I note with interest that there are entire websites dedicated to errors made by QI, perhaps this one belongs there