I too find a 4 character limit to be too restrictive. I was raised on Original flavor D & D, and the AD&D 2.0, and truly enjoy the addition of support classes beyond the 4 major food groups - adding a ranger, bard pallie or such provides more variety. And while some folks want to enjoy the replayability enforced by a 4 person limit, some of us have other responsibilities that limit our play time. I've been playing one single run of PoE2 since release, and only just hit lvl 17 on that first play through. Work, family etc. take up far too much time for me to ever play 100 different BG3 run throughs.
My DOS2 game uses the mod that allows me to use additional group members, and if Larian doesn't add that to BG3, I expect to grab the first mod that allows that flexibility. My time is valuable, and what payed for the $60 I handed over for the game.