Even in its Early Access status, BG3 is already chock full of content. It is already abundantly clear that replayability will never be an issue, so I think there is very little reason to cut us off from all but 4 companions (or worse, 3, if we do not choose an origin character, and their stat block is not ideal… especially Shadowheart’s).
DOS II did something similar, but they had only 6 playable characters to begin with, and there is reason to suspect BG3 will have more. We are already at 5 official companions.
I know Larian seems quite deadset on making us choose, but I hope they will reconsider.