If we're going to compare then we should do it fairly. The original BG games were made more than 20 years ago, and on budgets that--even adjusting for inflation--were a tiny fraction of BG3's budget. So it is eminently reasonable for me to have expectations of BG3 that greatly exceed what I got from BG2. Eight companion choices, some of whom may even be locked out after Act 1, is utterly piss-poor by any standard.
What about Planescape: Torment? It has some of the best companions (personnality/banter/interaction/quests) of any RPG ever, DnD or otherwise, and there is only 7 of them, some of them available mid to late game and most of them being really memorable. People seem to forget that
Bioware Black Isle had taken the approach of ''less but better'' concerning companions with PS:T, wich was the exact opposite of BG1. I hope/think that Larian is going with the same approach with BG3, as I greatly value quality over quantity.
Honestly, there is about 1/4 to 1/3 of the companions in BG1 and BG2 that I never took in my party in over 20 years of gameplay.