>>53224971Diglett and Dugtrio were designed with a 2D sprite-based RPG in mind. Back then, they didn't have to think about how Pokemon would function in different environments or situations.
After the anime and 3D games like Stadium became a thing, they stopped designing Pokemon like that, which is why even in its debut gen, Hippowdon wasn't submerged in sand in Battle Revolution or in the anime, only in its 2D sprites and Sugimori artwork.
