>>43876465I think level scaling is a good addition to the series, if done right. But there are some major pitfalls I can see if they just half-arse the implementation.
1) If it's just based on your opening party member's level, you can start with a level 1 Pokemon and just switch to a higher level Pokemon to sweep everything.
2) If it's based on your highest party member's level, having a single Pokemon which is a few levels higher in your party will make it difficult to battle anything with the other party members. Although I suppose this can be seen as a good thing since it encourages you to keep a balanced team, it can also encourage you to just stick with a single Pokemon. When you combine it with the Exp Share and Sword/Shield's experience scaling that gives weaker Pokemon more exp. when you defeat a stronger Pokemon, it should help bridge the gap between levels anyway.
3) As Pokemon level up, their movesets improve and they evolve. If the levels are the only thing that changes, you'll end up with underlevelled evolutions with much stronger stats and moves that are much stronger than the usual tackle/ember/water gun/etc. that low-level Pokemon start off with. This can be mitigated by giving trainers different teams as well as scaling the level, but that might be considered too much effort for Game Freak.