To put it simply, "Scarlet and Violet" is a step forward for the series in some ways, and a step backwards in many more ways. For reference, I played Scarlet.
Everyone has already discussed the graphical and performance issues, and yeah, they aren't wrong. While they didn't ruin my experience much personally, these issues are still inexcusable. The Switch is very much capable of running beautiful large open-world games, meaning that this is not a hardware issue, but an issue with Gamefreak, the developer, who is not equipped to make this sort of game single-handedly.
But the issues go beyond performance. Many of the quality-of-life features that Legends:Arceus gave us are gone. The open-world structure of the game doesn't mesh perfectly with the pokemon formula (fighting gyms in an increasingly difficult order), which is inherently a linear path (there were multiple instances where I mistakenly challenged the gyms, titans, and/or bases out of order, making them either too challenging or no challenge at all). Most of the gym tests weren't very fun and felt tedious. Nemona is a very annoying, shallow rival. And while there are a few bangers, a lot of the new pokemon designs don't really resonate with me, especially the new regional forms.
However, it isn't all bad. While I wasn't sure about it at first, terastallizing is a fine mechanic. When it works well, it's great, and when it doesn't, it doesn't really affect your experience that much. Also, Arven's story and the Titan battles were among my personal highlights for the game, as was the fight against Team Star. The Ghost-type gym was my favorite. The game gives you better access to mints and held items that make it easier to tailor your pokemon team to your liking. The picnics aren't bad, though I still prefer Sw/Sh's approach with camping and playing with pokemon and making curry.
Full disclosure, I have yet to finish the game's story. And in all honesty, I have certainly been enjoying my experience with this game overall thus far. But the issues that it has just feel as though they're very easy to fix, especially since those issues are mostly just downgrades from features that already existed in previous games. I like the game, but I only tolerate these issues because S/V is very innovative and new for the series. I would not tolerate it if these issues persisted into future games.