Because there were lots of useless vacuum cleaners that did come with 3kw or larger motors. I even owned one which proudly displayed 3500W across the top of the cylinder in big writing,. it was **** compared with the 900W Miele I bought to replace it.
Hence your whole analogy of a less powerful vacuum cleaner takes longer to use and hence overall power consumption is the same is flawed.
And why is Dyson only using 500W motors in his vaccums atm if the EU allows 900W? Surely he should be putting 900W in them if bigger is better like you claim? Or perhaps he knows better than you and the things he said about the EU on vacuum power rules was just to get the UK to leave the EU for other reasons that suited him??????
You are right, its a GPU thread but last thing on the subject I am going to say is I don't dislike Dyson, i think he is a brilliant inventor, exactly what the British are good at. But equally i can dislike his politics of wanting to get rid of regulation and the NMW and having people work in the UK in his factories for less than £5 an hour because they wont have any choice, it will be do that or starve.
The world isnt a black and white place. You can come up with the cure for cancer but be a peado and rape kids.