Problem is that Larian apparently decided to not lock out people of content because of their choices, so no matter how much sense it would make drow and gith will face no restrictions at all in act3 apart from meaningless one-liner before the regular dialogue starts again.
Well, it's bad decision then. For example drow is OP in act 1, why not balance it in act 3 and make some interactions difficult for them. Force to use disguise spells, charisma checks and so on.
