Legends Arceus or whatever it was called could have been my favorite Pokemon game but they took so many weird decisions and made it a chore instead of fun and as always made it super baby mode and didn't go for any kind of online options. A good 3D Pokemon MMO is possible, but Gamefreak and Nintendo don't seem to have any interest in one ever existing. Also, I'll be honest, I see no reason whatsoever that they limit the Pokemon available and cut old ones, with all the money they have and employees, there's no reason they can't incorporate every single pokemon into newer games and in an MMO setting they could even do certain ones active at certain times or some other way to make them feel exciting to get.