Of course pokemon are going to be removed from the game, it's quality over quantity, they're focusing on pokemon that are available IN the fucking game so that more can actually be done with the game. Why would they waste development time on pokemon that aren't in the game?
You idiots are just used to nintendo working on shit the average player will never even be aware of like extra sprites and models for pokemon that aren't in the fucking game (pokemon gen 3). They're doing right by you and right by Pokemon