All trueYeahh... the Company would lose too much money that way. And it's very illogical.
1. There would be no point in making other games if al of the regions were in 1 game.
2. The level cap would have to be raised wayyyy past Level 100.
3. The trainers, gyms, leagues, and wild pokemon would be at too high of a level toward the last 3 regions.
4. It would take up way too much space in the game cart and all of the regions would be watered down (ie. look at Kanto in HGSS)