>>54834727>>54834809The real reason Kanto is cut down is one part streamlining and one part plain running out of time to ship the game. Routes were shortened and the Viridian Forest was removed because frankly traversing Kanto should feel shorter to a Pokemon Champion. Viridian Forest is superfluous. Even in HG/SS it serves no function other than to fight the same dipshit mono bug type trainers with three Pokemon just with level buffs.
Other places were clearly intended to be included (Safari Zone, Seafoam Islands, Cinnabar Island-as-a-town, Pokemon Lab, Pewter Museum, Lavender Tower) but were cut due to time constraints. This map from the middle of Gen II's retooling from the Spaceworld Nihon region to what it became on release is telling. There are maps for many of these areas lurking within the game files.