Ka-pi96 said:
Because Nintendo do? The fact that they only ever released Gameboy sales including the Colour rather than separating them kind of suggests that they considered them as one platform. |
They did that because they weren't expecting GBA to be delayed so badly so were already lumping their sales together early on expecting GBA to come out soon, when the GBA got delayed GBC became its own platform even though they were already lumping the sales together.