So I've played this game since launch and have overall enjoyed it. Much has been said about the story problems of act 3 but I have a position that will probably be far more controversial. I don't think the main story of this game really works at any point.
That's not to say there aren't good stories in the game or that there aren't good moments, but I don't think the actual main plot of this game ever hangs together as a cohesive whole. There are holes and confusions at nearly every turn, and when there aren't, then it's because the "main" plot is only string to justify going around places.
I overall agree, but couple point:
I don't think "plot" is that important in cRPGs. Plot tends to be a static think that drives players forward. I would even say that usually best RPG stories have basic plots that inform objectives but don't define the journey. Both Fallout1&2 plots revolve around finding a McGuffin. Fallout New Vegas plot goes "find guy who shot you" and "resolve local conflict". Planescape Torment could be summarised as "find a way to die". Entire Disco Elysium revolves around solving a murder.
There are of course RPGs with more linear elaborate plots, but BG3 plot vaguely boilind down to an overarching objective per plot isn't in itself a problem.
The issue I have is generally those plot light titles that I mentioned tend to give players a lot of narrative urgency - define the character, their relation to characters they meet, how we solve problems that arise are narratively impactful on our character. BG3 (and Larian games in general) offer really cool systemic freedom, but actions we take rarely have narrative importance. There is reactivity, but that reactivity tends to set the narrative back to pre-determined outcome rather than react to our action in a thematic or narrative sense. There are choices with narrative impact, but those are few, and personally I found them shallow and uninteresting.
Than there is an issue of quality of those overarching objective, and if they gel into cohesive whole. Due to EA a lot have been said about conflict between the urgency of the tadpole and relaxed exploration. Personally, I found act2 the weakest - mostly because it revolved around a backstory for a character we don't really get to interact with. If there was an interesting decision to be made regarding Thorm, perhaps it would feel less like a waste of time to me.
I actually thought act3 works the best - yes it seems to take a sharp turn from previous acts, and especially ending seems to suffer from it. But I thought it worked the best. We are in posession of one of the stones, so enemies can't proceed without it, and our goal is to gather allies and get a hold on other two stones. While not ideal, it is still best balance between urgency and reasons to stall that the game had.
What kills the game for me, is that it lacks thematic core. Originals, while very simple and basic, and a clear throughline of embracing or resisting evil within you. BG3 plays with the same concept - in form of embracing or rejecting the tadpole, but it is not always there, and in the end it doesn't matter, and I am not sure why would one ever feel tempted to embrace it. I think Emperor is there to do just that, but I don't think he helps in selling the idea and comes way too late into the story. To me BG3 feels like a compilation of various different ideas - like they have thrown bunch of ideas together, but not with enough case as to how they will fit together.
Narrative is just isn't strong point of Larian's development process - that's why I believe D:OS1 who simple didn't care to tell a coherent plot is still their best RPG. They can have a staggering amount of voiced content, and cinematics, but I just don't think it is a very good content. The most fun I had with BG3 was playing around with systemic sandbox, and the most frustrated I was when I tried to connect with the narrative. It is fine to do your own thing. For the last two games, I feel Larian is trying to pursue the complete opposite of what their design is good at.
