>>54516138And the only major city with urbanized structure and technology is Goldenrod. Contrasted with the almost entirely urbanized Kanto, Johto is a majorly rural forested region, like how Hoenn is a majorly tropical region and Sinnoh is a chilly, windy region with an extreme mountain range. But if identity hinges entirely on the proximity of other regions and literally nothing else, then you could call Kanto East Johto as much as you could call Johto West Kanto.
But really, I think the fact that the two regions share a road with each other is ultimately a non-issue. Johto being next to Kanto doesn't make Johto any less of a region, and Kanto being next to Johto doesn't make Kanto any less of a region. They just coexist.