I disagree with the argument that says the lack of newer types limits GameFreak's creativity when it comes to bringing in new Pokémon. You can't really say that when there's still a number of type combinations they have yet to use.
I never said a lack of new types limits Game Freak, but you can't argue that adding a new type doesn't open new doors for pokemon creation.
I understand the type match up problems that adding a new type brings. I'm just trying to bring a different view to the equation.