Do you think Paul has the potential to appear in the anime again, or do you think we probably won't be seeing him?
Gary, of course, continued to re-appear in the anime from time to time after Ash beat him at the end of Johto. Part of this could be because he was the original rival of the anime, so the writers kept him around in some form even briefly. He is also related to Prof. Oak, a character who is always there.
Paul isn't connected to any Kanto character, nor does he have the nostalgia that surrounds Gary (whether its deserving or not). Other rivals have similarly disappeared off the face of the Earth, we probably won't be seeing May or Dawn's rivals in speaking roles ever again, and the likes of Barry, Conway, Nando, etc. probably won't ever return.
But given Paul was a major rival, what do you think? Is Trip essentially making it seem like the writers have moved on?