Pfft.
O rly?
Is it not, in fact, the exact opposite? You know, along the lines of: a numerical sequel number infers a product is a direct sequel to the installments that came before it and logically contains large segments of commonality.
And?
Are you getting to a point? Or did you just feel like typing?
(They're nice straw-man though. Way to go.)
Right, because the events of 'Baldur's Gate 2: Shadows of Amn' took place there too. Oh, what's that? They didn't?