Established high level leader type characters de-leveled to become low level companions. It's level scaling at it's worst and undermines any structure of power the world might otherwise have.
The world needs powerful NPC's. Much more powerful than your party, especially when you are starting out. They are great at showing you what you have a chance at becoming if you succeed. It's motivational.
High level NPC's can be very powerful plot devices. Imagine a high level NPC sacrificing themselves to save your low level party because you are "special" somehow. Stuff like that is almost required to really hit a home run with a narrative that involves you being special. Instead of someone just saying so. That's how Gorion was cleverly used in BG1, even though he was "just" a 9th level Wizard. A high level NPC riding in to save the day when things look hopeless can also be powerful.
High level NPC'S are very much needed to establish a credible power structure in the world. I.e. what do the levels even mean? Who is weak, who is powerful and who is somewhere in between. If Halsin, Minsc and Jaheira won't be allowed to be powerful, who then? If Larian are going to de-level Jaheira anywhere below level 15 in 5e, I'm not going to believe she's the epic Druid who fought Firkraag, Jon Irenicus and Demogorgon. Why undermine her legacy like that? I like Jaheira and always had her in my parties in BG1 and BG2. But in BG3 I want to play with a NEW party consisting of NEW characters. Jaheira deserves her status as a legendary NPC and a hero who can drop in to help you out but not fight the battle for you, because she has bigger fish to fry herself. Invoke the nostalgia in the RIGHT way. But please don't make me watch her getting downed by some level 5 enemies and helped 5 times whac-a-mole style in BG3. That would be utterly stupid and pointless.
I get the feeling that Larian don't understand the value of a power scale in the world. In their game level 1's are already portrayed as badass even though it's very clear they are not when they get one shot by the first Bugbear. There is a glaring dissonance between storytelling and game mechanics. It's like they're trying to make that connection go away. But it's not going to go away. And it serves no narrative purpose to pretend the PC and companions are the top dogs wherever you go. Save for boss monsters who get a few extra levels for a tough fight. Right now Halsin is the only friendly NPC we have met who can be expected to be at least level 9+, leading a big circle and being portrayed as a master healer and First Druid. But the storytelling has completely failed to present him and the circle as any kind of even semi-powerful entity. Hell, if a low level party of 4 can wipe out an entire circle of druids and it's leader, what kind of a "faction" is that anyway?
I'm pretty sick of this "amazing from level 1" nonsense and low level parties clubbing Adamantine Golems to death. I want my low level party to feel like a low level party. So that when I reach higher levels I will feel like I've made it. I would also like the world to show me NPC's much more powerful than me to create a dynamic and tangible power scale. I want to see characters like Minsc, Jaheira and Halsin take down some foe far beyond a low level me while I deal with minions. So that when I am finally able to take down that same foe, it will feel like a true accomplishment. Basic tools of good storytelling, really.
