I mean, you can't have an Int lower than 8 in this game, and that's just 'a little below average', and not an indication that you can't speak properly (PSA: 8 Int is not "dumb"). Getting down to 7 or 6 and you might be struggling, sure, but not at 8 or 9.
NW1 did alternate dialogues if you were below a certain intelligence, and while it was amusing in one way, it was out of place atmospherically...
Uncle Lester has a point, in that Larian's prospect on this seems to be geared more towards putting in as many skill checks as they can laden dialogue with, which will, themselves, represent more insightful, intelligent or clever things to say.
