I, whose first language is English, found that difficult to understand, even allowing for the vagaries of YouTube. The guy gabbles his way through the entire briefing, and I would love to know what percentage of those on board actually understood what he was saying, remembering that a lot of people in the US do not have English as their first language.
This kind of thing is whimsical - until something goes wrong, that is. I'm all for making flying as pleasant as possible, and I've travelled with Southwest a number of times, and frequently heard their jokey comments e.g. "If you leave any personal items on board, you can get them on eBay tomorrow," but there is a limit.