It must be said that the hi-fi industry is worse even than the stalking industry for selling total balderdash to people while maintaining that it will be "better" in some meaningless way which almost certainly contradicts the laws of physics.
My favourite all time "must have hi-fi gadget" was a birch volume knob coated with a special varnish which meant that when you removed your standard volume control knob and replaced it with this one your vibrations would be damped and your hi-fi would sound better. It was only £960 and we had the advert for it hung on the wall for a long time.