>Does the quote above suggest Alberto (AGD) is misleading in his saying his GANFETis made for audio?"
Alberto is correct. There is a large variety of GanFET transistors that are made for different voltages and currents and switching times. Only some of them are good for power amps for a number of technical reasons.
GanFET transistors in audio amplifier work entirely differently than let's say bipolar or FET transistors in class A or A/B.
They are just switches, there is no transistor curve involved in shaping the sound like in Class A or B.
GanFET transistor used in class D are just a better faster switches then MOSFETs traditionally used in old Class D. They produce a more square square wave resulting in bringing out all this magic otherwise lost in the grunge generated by MOSFETs. I wrote an illustrated primer paper on Gan FET explaining the mechanism in detail:
https://mytek.audio/shop/empire-ganfet-stereo-monoblock-introductory-special-free-b-amp-2#attr=11
Michal, Mytek Chief Designer