The main reason I prefer 4, is the fact that I would prefer to play as many characters as I would in tabletop: One.
I doubt many would agree with me, but I'd actually prefer a cRPG with one controllable protagonist per player (multiplayer) and rest being fully AI controlled NPCs. I don't play four characters at the same in D&D, let alone six. So realistically I'm indifferent past that initial preference đ It'd actually also increase my interest in companions as companions, because anything I personally control, I consider to be *my* character, not a companion. So by having control over multiple characters, it actually lowers the value I put in them as companions.
I'm weird.
I don't think you're weird. If anything the trajectory of D&D and Fantasy RPGs seems to have moved pretty clearly in that direction going on 2 decades now, with only a couple brief and clearly nostalgia driven titles going for the full party control vibe.
For my part, the defining characteristic of Baldur's Gate was the idea that the player was running an entire party, and not just their own character. The impression I always had was that this experience was not at all like the Table Top, or perhaps it was, sort of, but where the player is more of a pseudo DM/PC hybrid, as opposed to just a normal pnp PC. This worked in part, and especially as the game got going, because the campaign was about the rebirth of a dead god, and so a godmode of this kind was sort of fitting. Also I think BG3 has the perfect set up to rationalize something similar.
The idea being that we're a actuallly a party of Illithid mind Worms in this game, and not really the PCs they're inhabiting, which are just like our hosts. So Tav is a worm. Lae'zel is a worm. Shadowheart is a worm... etc. We're all worms! A party of tadpoles, with a connected awareness, shared sense of collective experience, and POV. It actually works quite well I think, if they'd lean in. It's not that Tav was infected by the worm, but rather that Tav is the worm. I think they could run with that.
There are many reasons I want a party of 6, all covered in the mega thread many times. Not 4 or 5, or 2 or 3, or 10 or 20, or 1, but 6! I think it's unfair to characterize this as slippery slope situation, or a 'don't give an inch, or they'll take a mile!' sort of deal, as suggested in some counter arguments. This is clearly a popular or at least oft repeated request, compared to many others floating around. Though I'm sure it will be merged again like the others, there's a reason this thread re-materializes every couple months. Just to reiterate, I want 6 in the base game, and I want it work smoothly, not as a mod that potentially breaks other things along the way.