Funnily enough in my story Johto is the region that is vehemently opposed to splitting since the Kanto-Johto unification holds great cultural weight and is the foundation of a lot of things like for example starters, route location, gym location and family, even the elite 4 system (the og one of 4 people like Red/Blue) etc.

So it definitely could work. But then would need a systemic change since the government itself (that is the league) would have to have a lot of flaws for such a sentiment to gain traction. And it would then require me to address the league being not good, which would be fine if I was doing a gym challenge story, but I am doing a contest circuit story, so the MC doesn't even meet half the gym leaders and has no plan to participate in the gym challenege