As someone who grew up with a pal N64 and the first computer for videogames having been a shitty laptop struggling to run Morrowind at 30 fps, I've absolutely no issues with the performance of those games. I play it on a lite and I'm having a great time. The issues like shadow pop in and frame rate dips are entirely irrelevant to my enjoyment of finally having a true open world pokemon the way I'd hoped we get back for the n64 when they announced pokemon would finally be in 3D.
So far all I've encountered in issues were purely cosmetic and did nothing to impede game play, and a lot less of an issue like most TES games had shortly after release.
I'd personally suggest emulate it for an hour or two to figure out if you like the game, and if so buy it. While I won't accept anything less than perfectly stable frame rates for stuff like racing games and shooters that hinge on split second reaction pokemon is so slow paced it's entirely inconsequential that the frame rate drops at some points. You're not going to miss a dodge, fail a jump, or take a bullet because of it.
Edit: otherwise the game is pretty good, you explore, you catch Pokemon, you beat up other people, rinse and repeat. The clothing choices are bad but that's about the only thing I genuinely dislike so far. Otherwise it's finally a nice experience where picking up an item doesn't take a minute telling you what you picked up and where you shoved a thousand times in a row.