I haven't encountered any game-breaking bugs, but modern Pokémon games (Shield and Scarlet) have maybe the worst moment-to-moment gamefeel of any AAA game in recent memory.
Every action (battle animations, menu selections, cutscenes) takes about half a second longer than it should, the cuts between camera angles are, inexplicably, crossfades (about 90% of the time, anyway, with no discernible reason to choose a hard cut over a fade), and the game is doing the now-standard "3 hours of tutorial" thing (although to a lesser degree than Shield). Movement feels sloppy at best and downright janky at worst. And the lack of shadows on most of the environment art is really starting to wear on my eyes.
Pros so far: over the years, these games have really broadened the palette of possible Pokémon you can encounter in the early game. No more grinding a weak-ass Normal/Bug/Flying team for the first several hours! And having an encounter with a legendary(? at least it's the cover-art mascot) Pokémon early on is a fun development.
Oh, and the NPCs are only getting cooler. Check out the buff Hiker ladies if you get a chance. Someone on the art team is absolutely putting their whole heart out there.
The "they're games for kids" excuse doesn't fly for me anymore! Plenty of games aimed at younger players, of higher and lower overall caliber, don't have issues like this. I imagine the development team needed more time and assistance to polish/improve the performance of pretty much everything, and clearly couldn't get that. Nintendo needs to get that late 2022 profit, after all!