Kidding, really $400 is a little much for a blow dryer even a Professional one, Mom is a beautician for longer than I have been alive, she says about $200 is about top end on a good dryer. Not sure these will sell on the street for that much.
And I thought it was going to have an engine not a motor? A motor converts electrical energy into mechanical work. An engine converts thermo chemical energy or heat energy into mechanical work.
Though I would have no use for a hair dryer let alone one of this price. I could see people wanting this if it really is more powerful and has a much greater lifespan. Assuming stellar build quality and lifespan I would equate this to a Kirby vacuum cleaner. Though $400 and $500 Hoover's (or whatever brand you choose) can get equivalent marks to the $1800 Kirby. Those vacuums are cheaply constructed and start losing power after a couple years. While the Kirby has a lifetime warranty and is expected to last 25 years before needing replacement.
If Ferrari stands behind this hair dryer as Kirby does their vacuums I could see a market for this. Otherwise it would be quite a waste. As the 500-700 hours for a normal hair dryer is likely those $50 units not high end $200+ units. Though at that price they should have used aircraft grade aluminum for the housing.