Not much fun to make a character from wherever (this is DnD, there is supposed to be freedom to make almost anything,) avoid all the Baldurian tagged responses, and then get all the way to Baldur's Gate and find out that no, you are not allowed to be from where you thought you were.
I strongly hope the same, i.e. that the game will not force us to be from Baldur's Gate.
Given how much freedom Larian has been giving us so far (cf the non-sensical race-locked dialogue options, or the Astarion scene in Patch 7), I don't have too much faith. But if our opinions count for anything (which is not clear, but let's hope), I'd like mine to be recorded as :
I don't want to be forced to hail from Baldur's Gate, even if my PC is Human. And I likewise don't want to be forced to be from the Underdark if my PC is a Drow Elf.