Some good points here.
I believe in the US it was the sales of "extra suction power" (not the "ESP" by Eureka, but similar context) that got consumers mad on trying to outdo each other with powerful vacuums, but more to do with brands versus brands in the board room and trying to outdo the other. Since then, mostly all brands have been competing with each other on extra suction power, extra motor watts.
The way things are going with that new Vax Mach Air Cordless and the Bosch Athlet means there may well be more cordless vacs in the future as well as robotic discs to take care of home dust - and possibly only once or twice a month would be required to properly vacuum a home - now wouldn't that be a slap in the face for all those brands eager to keep selling vacuums and replacing them with a new model several months down the line?
I don't have any fears about the changing industry in floorcare - for the most part the commercial market is steadier than the domestic one and even if, in the future manually vacuuming may well become "vintage," at least there will always be a variety.