Proving that two things sound different doesn't prove which one is better. You know how speaker cabinets go to great lengths to solidify and stiffen the cabinet walls internally so they don't vibrate?—the air's excitation from those panel vibrations have a name by the way: distortion. See the only thing that's supposed to create the music sound is the drivers; not anything else in the vicinity vibrating sympathetically.
Well besides using internal cross bracing, buttressing, thick heavy walls, corner reinforcements and other methods to reduce cabinet shake, one of the easiest forms of cabinet shake reduction is to bolt the cabinet securely to your solid/heavy and immovable wall or floor. What's that? You don't want to have to drill holes in your floor? Well that's why the speaker came with spiked feet so the product's own weight will securely hold it in place and rely on your hard/heavy floor to help minimize the cabinet shake. [If you fear the spikes will mar the floor then place a coin under each one.]
Instead floating the speaker on springs, rubber, magnetic fields, etc. reduces the added solidity it gets from being held firmly by the floor and INCREASES cabinet shake hence increases distortion.
Another aspect often overlooked by people testing these various isolation pads is that a speaker's sound changes slightly by moving its room placement and YES just raising it an inch or two counts. Ethan Winer has a great demo of this:
https://ethanwiner.com/speaker_isolation.htm
P.S. The only scenario where placing your speakers on a wiggly rubber platform would be arguably beneficial is if your speakers supporting table/stand/etc. is just
so rickety and flimsy its sympathetic vibrations and loose screws are causing a racket, so decoupling from it is a higher priority than what the speaker's cabinet walls do. . . . Me? I'd tighten those loose screws.
