Ooooh. A Traitorous Battle Royale? I wonder if Ash gets taken out early because he has the reputation of Alola League Champion and everyone teams up against him?
Or Incineroar gets mad because he's using Pikachu or something.
I recall the common speculation was that Ash has become so famous as a powerful trainer, now recognized as part of the Master Rank class, that everyone in the Battle Royale team up to defeat Ash because they think he's too powerful. And I believe that is case.
Ash has been the underdog for so long that he doesn't realize he's no longer that underdog rookie anymore. He's a Champion, and Champions always invite challengers whether they like it or not. And it would be even worse if Ash still beats them anyways because it will show that he's a whole new level now.
Recall that Ash was eager to battle anyone who challenged him. Recall that he was always happy whenever he won. And recall that the battles were always exciting even if Ash is clearly favored to win. Now, those battles will end quickly because Ash has gotten that skilled at Pokémon Battles. Now, people don't battle Ash for fun anymore. They just want to win at any cost. And if they still lose, then what tension is there left? Who would give him the rush of excitement and push him to the limits?
He's starting to feel what Leon is feeling as Champion. The utter boredom of winning and never finding anyone worthy to fight. And he can't hold back or try to make it easy for his opponents. That's not pushing the opponents to their limits as well. Both have to give their all if he wants to feel the joy of battling. And there be the dilemma.