Are future improvements in Amp/PreAmps slowing to a crawl?

I could tell you what it sounds like. It sounds like no amplifier is in use.
As far as performance - It's more like a 3D sound projector.
The only thing you hear is the original venue fully "displayed" as an acoustic image. Turning the volume up and down acts as a zoom control that changes the distance or your proximity to the performance.

bad tracking with channel to channel variation would harm spatial cues