They aren't wrong, as it's their story. But it can and should be criticized.
Hopefully they don't do a Bioware, and publicly shout their "artistic integrity" defense.
Yea I really hope they don't start shitting on the community for not being able to see their brilliance. That being said if this was a linear game I'd agree with you about their story and their narrative being theirs alone. But bg3 is player decision based and is guided by the decisions of individual players. The idea being that each player can sort of create their own story within the simple idea of "ok you got a tadpole in your head and this weird artifact. What you gonna do about it?". That's all ripped away when karlachs story is railroaded from the start.