Good for Ralph...life can't just be about music and Gear 🤣.
I can't seem to find it now but I think Ralph said that his goal with the Class D Monos was to get the distortion as low as possible and be sure that any residual distortion was dominated by the 3rd Harmonic....and based on how you describe the sound, I wouldn't be surprised if this is exactly what Tommy Obrien was doing at Cherry Amp...although he never actually said it.
What about the wattage draw question...if a class d amp is 90% efficient, does that mean that it draws 110 wats to produce a 100 watt output?