Cultivators were just people, so naturally, they also possessed the seven emotions and six pleasures, and tended to think of themselves as superior to others. Such a feeling of superiority would often turn into a type of happiness.
Oftentimes, that feeling of superiority really is… the source of happiness.
For example, the feeling that you are safe while someone else is not, can be happiness. Another example would be drinking a cup of water when you are thirsty, while someone else has nothing to drink except their own saliva. That can also be a kind of happiness.
The people in the boat were currently experiencing exactly that type of happiness.
Because of such happiness, they were not as nervous about the danger that surrounded them. Instead, they were laughing and chatting about the unlucky fool on the outside who had overestimated himself.