In most cases if Larian would come out tomorrow saying "Yeah, we decided that a 4-men party blows unwashed ass because it doesn't give you many chances to interact with more companions" you'd have the same people jumping on the cart and switching their tune to "I'm glad they changed it, I prefer to control a larger party as well".
That is what really grinds my gears, the fact that so many just repeat the same debunked arguments in favour of a party size of four, would immediatly change their tune if Larian implemented a party size of six. It's almost as if they have a physical need to be on the perceived side of the developers.