I am not sure I agree with that Alex, because Candy took over Hoover around 1993, but the Autosense feature carried on long afterwards and right into the Hoover Purepower, because in the original 1997 Purepower collection there was an Autosense model. Personally, I always thought that the removal of certain features was a way of bringing down costs and / or introducing a lower specification cleaner to the market.
What needs to be remembered is that so much has changed to many aspects of life in the last fifteen or so years, due to the internet. This has affected the way we buy anything, not just vacuum cleaners, but as far as the vacuum cleaner market goes, the impact of the internet coupled with the rocketing sales of the early Dyson models has turned it on it's head. Then there has been the dramatic drop in the retail price of almost all electrical goods, and that price difference has to be recouped, be it through the removal of parts and features, or moving production abroad, or whatever else it takes. So it would be impossible to pin-point a specific reason for why vacuum cleaners are being made the way they are today as there are so many factors which need to be accounted for. But the fact remains that whatever we experts think of a cleaner, that same cleaner will have been built the way it was because (A)it is cheap (B) it works and (C) it sells.