Quoted By:
Silver starts as an ass, and the game treats him as someone who needs to change. The game is effective in making you want to win against him specifically. You're the first person to notice him looking through the lab window, you get pushed by him, and you continue to encounter him at multiple points in the story, giving you a sense of equal progression. You see his character evolve both through his dialogue and his team, from stealing Pokémon (starter, Sneasel) to befriending them (Crobat). Later games recontextualize his personality. It answers why he hates weakness, why he has it out for Team Rocket. All in all, he feels like a character who goes through an arc.
Gladion is edgy, but it's more like a style rather than him being an actual jerk. His torn clothes are because of him taking care of Type: Null. He's overly serious for a kid his age, and a lot of his traits have chuuni elements to them, like his posing and hand gestures. The "Hmph" is more of an act than genuine, and it feels like he exists more as a foil to Hau. He just doesn't hit as hard for a rival as previous serious rivals. If anything, I think he'd make a better rival to Hau than to your character since he reacts to Hau more than you. I also don't get the sense that Gladion grows much during the game. He has more friends by the end and his family is mostly restored, but he still seems like the same guy overall.
