>>46380371No it’s not this, it’s because Rowlet and Oshawott were obviously brought from a faraway region by travelers to ancient Sinnoh, they probably grew old with their trainers and never had the opportunity to breed with their kind. And since dittos weren’t created yet and the starters are all male, no more of those Pokémon could be created in the region leading to their extinction in that particular zone!
Simple zoology
