Wow, this is just so typical.
Here your correct, and we probably all agree.
If you really want to get the soundstage right, the amp needs to have minimal phase shift in the audio regions so it will need bandwidth past 80KHz. Most larger SETs simply can’t do that!
Neither can Class-D because of it’s switching frequency and associated output filter to get rid of it, that brings phase shift down into the audio band as this shows in red. https://ibb.co/sjNy1Fq
Over here https://forum.audiogon.com/discussions/gan-based-class-d-power-amps you say the opposite, because you have a Class-D coming out.