I am not sure where obsession with the switching frequency comes from. It is inaudible while the only other thing that it might cause is filtering network phase shift - that can be beneficial since speaker has much larger positive phase shift at high frequencies. Placing nonsense about signal being "destroyed" (while SACD works exactly the same way) is trolling.
In fact raising switching frequency might be harmful because of the dead time, forced by the controller to avoid shoot thru, that Atmasphere mentioned. Since this time is fixed, error it makes will be larger at the higher frequency. One might not like the sound of particular class of amplification but making pseudo-scientific explanation i plain silly.