Is it me, or does it seem like the Kanto-Johto superregion hold a lot of influence over the rest of the Pokémon world? Like, Poké Balls started in Johto, then modernized, industrialized, and commercialized by Silph Co. in Kanto (who also made the Master Ball). The Kanto and Johto Professors created the Pokédex and discovered Pokémon Eggs, respectively. The PC system was first invented by a Johto guy who also works in Kanto. What’s going on here, from an in-universe perspective?
I’m hesitant to assign too much importance to something that has a really obvious real-world explanation – i.e. those regions were first, and in Pokémon’s early days there was no certainty that there ever would be other regions, so we find explanations for a lot of important core concepts there. Also, like, Bill gets a lot of the credit, but every other region has a tech expert who’s supposed to have worked on the PC storage system with him. Pokéballs… well, there are regions that still don’t use them, right? Like Fiore, and Almia. And Pokémon training predates Pokéballs, probably by quite a bit. Wherever the first ones were used (which I agree is probably Johto, though I don’t think that’s ever actually been confirmed officially), the convenience of the new technology probably caused it to spread very quickly, with little deliberate drive from the creators, and the lifestyles and ways of Pokémon training associated with the technology would have spread too. Pokémon trainers of the world might have been a much more diverse bunch before Pokéballs were introduced.