I think we are talking about Lego here... of course they can't replace paper & glue models. :(
That is why I have said that "taken on their own terms" as Lego bricks they can give a good stylized representation of the buildings. You can't make a trombone sound like a violin, can you?
And I won't go so far to say that the form is the most important element in every building; only that I don't find it unreasonable to emphasize the forms of those particular buildings in the series.