>>50769381The whole point of a Champion is that they're the strongest in the region. You can't be called a Champion if there's someone stronger than you out there.
Plus I'm pretty sure the same thing is implied in the games too, with Caitlin moving up from Frontier Brain to Elite Four member between Gen 4 and 5. They just seem stronger because of their gimmicks and being given legendaries to make then more challenging in-game due to being postgame.