First of all, the game isnt anywhere near as bad as people say it is.
They like to talk about all these crazy game breaking bugs. Many of them are fabricated and most of them do not happen to 99% of players. The only things you're likely to encounter/notice are 1. framerate drops (which only happen in a few heavily populated spots. Ya know, like most games do on weaker hardware) and 2. If you intentionally move your camera against a wall and make it move towards your character your face MIGHT disappear, leaving your eyes floating in the air. I guess genz kids aren't aware this has been a thing since the very first 3D game. And 3. there are awkward moments where your pokemon might run off, or something might fall off a cliff, etc. Your pokemon immediately returns to its ball if it does this, so it doesnt matter at all, and if you happen to miss out on catching a pokemon you wanted because of this, guess what? Theres literally hundreds of them all over the place. Nothing is hard to find.
People are doing what they always do: overreacting to nothing.
That being said, I personally find the game to be a disappointment in terms of design.
1. The aesthetic is terrible. It does not LOOK like Pokemon. I'll never understand why they thought we wanted to look like a 6 year old on their way to daycare.
2. The open world is poorly designed. Its massive, but its EMPTY. The ONLY two things to see in the world are 1. massive hordes of Pokemon (which makes them all feel generic and its not exciting at all to find a rare one because theres a thousand of them all over the place) and 2. the raid battle nodes.
No puzzles. No side paths to explore. Just wide open empty fields as far as the eye can see.
3. The freedom of exploration ruins the game BECAUSE areas have set levels. So if you go too far on one side of the map then go back to the other, then the wild pokemon and the GYM LEADERS will be vastly lower level than your team. It further removes any challenge that could have been. But thats the trend these days, I guess. "Gamers" no longer want to challenge themselves. Its sad.
4. The models suck.
Most Pokemon look like balloon animals. Or like they're made from pool float foam. Its not a good look. Also, most Pokemon are TINNNYYY. It's almost impossible to move from point A to B without stepping on a hundred 1 inch tall creatures.
5. Tera Forms.
While I do like that they add a defensive mechanic to the game, the hats just look stupid. Also you can only do it ONCE per battle (not that it matters since everything dies in one hit anyway) and it literally ONLY changes your type. It was a good idea, but it could be much better.
Overall, I dont recommend the game if you're an old school fan. It does not feel rewarding to play. Exploration is boring. Environments are bland and unimaginative. Towns all feel exactly the same (oh, you cant walk into building either).
Its just not POKEMON. It feels like a Mii game.
If you just want to play the newest game and you dont care about those things listed, you'll probably enjoy it. Otherwise I'd say just skip it or grab a used copy somewhere for 50% off.