>>39115022I'm going to assume that you're talking about Hau.
Sure you can prioritize having fun over winning, but you have to make sure that everyone is on board with that. Hau was doing it at the expense of his pokemon having a shitty time. The island challenge was also their journey, so when he kept on going "haha lol that was fun," they started to get pissed at him. Imagine if your boss had the same shitty attitude and caused you to fail. Not all the time granted, but whenever you wanted to do something big. (E.g. fighting the M.C. or Gladion). If you failed and everyone was trying their best, that's one thing, but with Hau pre-Aether, only one party was pulling their own weight.
The happy attitude was also sort of being used as a cover up for potentially being sad when he lost which isn't the best attitude to have. This is why it's probably for the best that he ends up crying after his league loss. He's fucking sad, but that's because he tried and actually cares.