I honestly don't understand the hate. This is honestly a super faithful recreation of the original with some major quality of life improvements, my personal favorite is being able to swap Pokemon with the boxes from anywhere instead of just at a Pokecenter. The game feels tailored for online battling as they made it really easy to customize your Pokemon's EV's and even change their abilities. The underground got a huge revamp and makes collecting mons more interesting. I can see why people are upset about the limited national dex but I honestly don't mind. I think people forget that this is a gen 4 game and as such has a gen 4 dex. I understand that other remakes have had bigger dexes but I'm sure this is because Gamefreak wants to keep Sword and Shield alive and wants players playing both.
My only real gripe is the same as many, the EXP share. On one hand its nice to not have to grind as hard for levels but on the other hand it makes the game a breeze. You can basically one-hit everything lol. My solution to this would either be to allow the EXP share to be toggled, or better yet, tune the opposing trainer's Pokemon's levels accordingly. If the trainers had higher leveled Pokemon, this could easily be balanced out. That's the only thing keeping me from giving this 5 stars.
Overall its a great nostalgia trip that keeps everything I loved about the originals but adds some great quality of life improvements. Cute game for casual players and a ton of awesome features for competitive players to make optimizing Pokemon easier than ever.