Some large panel speakers do seem to play best at moderate volume levels and not quite so well at both extremes of volume. But, that certainly is not the case with all such speakers. The old Quad electrostatics (57s) sound very good at low volume levels. I liked the low level performance of the Martin Logan Quests I owned years ago as well.
If you are looking for the very best low level performance, look at high efficiency full-range drivers and compression driver (horn) systems. I suspect that the reason so many of the giant horn systems that reside in the tiny apartments in Japan have something to do with the ability of such systems to deliver great sound at low volume.
If you are looking for the very best low level performance, look at high efficiency full-range drivers and compression driver (horn) systems. I suspect that the reason so many of the giant horn systems that reside in the tiny apartments in Japan have something to do with the ability of such systems to deliver great sound at low volume.