>>40397571Or what about this, they only semi-retcon them. Pokedex size entries become average size, and Pokemon that are fully eveolved or single stage can get bigger with increase in level. It would make sense for say a lv70 Charizard to be bigger than a freshly evolved one. Hell, the even sort implied that was the case multiple times in the anime. The Charizard island has many different size Charizard, and when Ash's first gets there his is very small on comparison. There was also the giant Dragonite in the OG season that was implied to be a cryptid of some sort, which means it was very old and thus likely very very high level.
Pokedex size should be an average or a starting number, not a set number