It reminds me of the Johto saga actually. By late Johto everyone gave up on Ash's boring Johto team of Bayleef
so the writers said, "Screw it, we're bringing back the Kanto starters!"
Claire's Gym was dominated by Pikachu
, Charizard and Snorlax
...all Kanto Pokemon. And then the actual Johto league had Bulbasaur
/Charizard star in all the matches while the Johto pokemon got limited screentime.
I guess everytime an arc is poorly received the writers bring Charizard in for the rescue.