Uhm, maybe the fact that Pokémon is the highest-grossing media franchise ever?
I keep reading this argument about how impossible it is for a videogame to deal with 1000+ creatures.
Yes, currently it might be impossible, it sounds extreme, and it hasn't been done before (I guess) but Pokémon is so important, and it's so successful, that it should be the one pushing these boundaries and make Pokémon the first videogame to achieve this feat. It's the least they could do as the most powerful franchise that there is in their area.
As I've said earlier, technology just keeps getting bigger, better and faster. New and more powerful consoles will come out in the future that will be more than capable to handle 1000+ creatures. But they've already decided that they've reached their limit in terms of how many Pokémon they're willing to deal on each game at a time, from now on.
If they keep this approach as they've threatened, we'll have to see how it reflects in all the other aspects of the games. In future games there won't be excuses if we don't have customized animations for every Pokémon when they make different moves (Blastoise's cannons problem i.e.)
Or the animation of physical moves, like having the actual Pokémon getting closer to the enemy to inflict the attack. The Regional Pokédexes have to look amazing in terms of UI, and so with every other menu, box, etc. Online features have to improve as well, the loading speed, the storyline content, the overworld design, etc. I don't know how many games we'll get this generation, but I suppose Gen IX will come for the Switch as well. If we don't see a huge improvement from SwSh to those games, then it will be very sad to confirm their lack of ambition.
I mean, after SwSh they will have all the Pokémon that appear there ready to use for any other Switch game within this generation. Let's suppose we get DP remakes next, with the missing Pokémon. They only have to work in the missing Pokémon that didn't make it to SwSh (and probably there will be still some missing after DP) and bring over the ones that were already done for SwSh. But I'm 99% sure they won't, because by what they said they just simply don't want to handle the ~900 at the same time on any future game.
As some people said, this is not an indie company with 4 people at a garage. I mean, in a way they kinda are comparing to the size of the franchise. They need to grow in number or outsource if they can't handle it by themselves. I repeat, the highest-grossing media franchise deserves it and is more than capable to afford it.