The issue isn't whether or not choices are being taken away, the issue is that this hampers roleplay decisions because the consequences of your actions are now not just narrative, they're mechanical. If I have 7 party members, 3 slots self not included, and lose 2 of them because of decisions I made, then I can at least make do with the companions I have left for party composition, and I still can roleplay even though I have fewer options. If I have 3 and lose 2, my party composition is in tatters, and I lose a whole lot of roleplaying opportunities that can't be made up for (theoretically). So I am now meta-roleplaying and compromising my character concept because I don't want my party composition to be gutted, and I dont want the rest of my playthrough to be comparatively hollow.

Now theoretically, that could instead add to the roleplay in that you are now making decisions in character to keep your companions happy, or you're taking on the hit to your party composition because "it's what my character would do." However, people are far more likely to meta-roleplay because it's the path of least resistance, and it would come off as that this is what the devs want you to do. (For context, I love playing manipulative characters so I personally have no problem with this)

So we're going back full circle to what has been said at least 3 times now, which is IF they can pull off this system while still giving the player more roleplay/party composition options rather than less, then the complaints are moot. Until that is shown or at least implied, then it's valid to raise concerns. The game will be great regardless imo, but there's still value in pointing out potential flaws.

Just for further context, in DOS2 there was little one could do that would sway a companion one way or another outside of direct conversation with them, losing one didn't give your playthrough much added depth, and the decision to have the ones not in your party composition leave forever was arbitrary and also added little depth (like I know why they did it but they could have honestly just put in generic godwoken and labeled them as such as opposed to showing the ones we were forced to abandon and it would've had the same effect), so it's not like there isn't precedent for concern. Again, it's not a problem for me personally, but Larian really ought to step it up if they're going to do this again because it's rather hollow as is, and people are retreating to the tried and true system of multiple inactive companions because that one is less likely to result in the meta-roleplay conundrum.