>>57824473When Pokemon started, real animals were needed as a complement. Remember, Pokemon was only planned as a single game (Miyamoto was the one who incorporated the idea of dual versions), and Johto was largely discarded content from Kanto.
They didn't really expect the franchise to be massively successful, so as it grew, so did the need for new creatures. At first, the replacement was gradual, but it reached a point where it wasn't necessary to have an Asian elephant when you have Copperajah, or to mention America when you have Unova and Alola, just to name a couple of examples.
Now, from a commercial standpoint, what do you think would be more beneficial for the company?
Pikachu playing with a bunch of normal animals, where the only commercial aspect is Pikachu, and that will quickly tire the public.
Or Pikachu with a bunch of new Pokémon that you can sell individually or as a set, different pocket monsters for different types of customers.
