I don't have a Switch, and thus haven't played SwSh, but based on my previous experiences with Pokémon games, I say that:
- ORAS, USUM and maybe even SwSh are exactly what I WANT from a Pokémon game.
To me, a good postgame is nothing more than "transform all the Trainers in punching bags", and because of how stramlined new games are, it makes grinding my reserves much easier, I can even do "Can you beat Elite 4 with a full Fire team?" type of challenges. This is far better than the crap known as Battle Frontier, at least now my Pokémon gain EXP!
And sure, a new region MAY sound like a good idea, but what's left after THAT new region is completed? Yes, exactly...
The thing about RPGs is that, at some point, you WILL run out of things to do, and there are two ways of solving that (assuming you won't just jump into a new game):
1) Create a new save file
2) Make your own challenges (like, say, S-Rank all the bosses, try new strategies against certain bosses, train your weaker members etc).
Those are the things I do, at least.
Story? Gens 5 and 7 were intentionally made to break conventions from Pokémon, which is why they have deeper stories: THEY ARE THE EXCEPTION, NOT THE STATUS QUO!
While the story of Gen 7 was great, I would be lying if I said I play Pokémon for the story, I play because I want to catch some monsters and put them to fight each other, nothing more, nothing less. Besides, I skipped the story of most Pokémon games because the screen is too small and I couldn't read the text.
Dex cut? You mean, the thing that's the STANDARD in the monster collecting genre? Yeah, it doesn't bother me in the slightest. A Mon game doesn't need to have the entire roster in order to be good, just look at Digimon (Cyber Sleuth only has 341 Digimon, there are currently over 1000 Digimon in the franchise). And in the case of Pokémon, when the alternative is just dump the Pokémon in the games' database and lock it behind transferring, the Dex cut is a BLESSING.