How is Aunt Ada Doom's manipulative efforts symbolic of the change that is occurring to the Starkadder clan?

Mr. Neck calls her on her lunacy act, citing it as an over-used and passé theme. It seems that change is on a roll and now there is nothing that Aunt Ada can do to reverse its course, so just as Aunt Ada Doom's lunacy act is passé , so, too, are the old ways of being for those on the farm.