>>51522250Experimentation.
Imagine you're a child who got the game, knowing nothing about the new (or maybe even the old pokemon) beforehand. You'll find something you really want to try out. Do you go "oh but I can only use 6 Pokemon" or do you want to give using that Pokemon a try over an early game shitmon or something?
Maybe it turns out you don't like using that Pokemon after it evolves or it turns out it was a shitmon like Unown.
Because of the wild Pokemon curve, the game actively disincentivizes you from this kind of experimentation, because training up a Pokemon is a chore in these games.
