I think a lot of the people focusing on the models are also discounting just how much work goes into pokemon on the mechanical side, especially when they’ve spoken about, and shown, an increased interest in the competitive scene. Even if you’re only balancing the highest stages, every pokemon needs their moveset reassessed, their abilities looked at and possibly changed, their stats looked at, and how all of this interacts with their typing, and all of this in reference to every other pokemon in the competitive scene. And then you have items like Eviolite that make non-evolved pokemon viable and that increases that workload enormously. This kind of work can’t just be outsourced or put on people new to the team (not that any other work can be, necessarily), and doesn’t account for mechanics like Megas and Z moves fans are sad to see go, or the Dynamax and Gigantamax stuff that takes their place. This all becomes more difficult the more pokemon you add. Which is what it is, because the fact is Game Freak didn’t remove however many Pokemon, they added hundreds that wouldn’t have been there otherwise. There is no version of this game that had every pokemon that they cut in half while twirling their figurative moustaches.
And then they still need to design the new region and pokemon and characters, make new assets and animations for those. And then populate the world with trainers who need coherent teams and dialogue localised into a bunch of different languages. And decide which items to place where, and which pokemon will appear where and what level they’ll be. It’s a lot of work, and introducing new members to the team isn’t necessarily going to make it go any faster, and the publisher is loath to allow a longer timeframe because of other merchandise being already lined up. Even if they could take longer, that costs more wages, which bosses don’t want to pay. It seems like a huge failure of empathy and appreciation for the work that actually goes into these games to be so angry that some pokemon won’t make it into this title.