If anything with the "high-end" I'd say price has less and less to do with quality it the further the price goes up and the more it has to do with making apocalyptic levels of profit margins. Even speakers, where the most difference typically occurs starts to get absurd when you cross the $10k threshold, IMO. It shouldn't cost $50k a pair to get good sound, at least not from the speakers. The problem is that even the best speakers can sound bad in a bad room and the room can take +/- 1dB rated speakers and swing them 8-12dB easily in some cases, especially in the bass regions.
One of my favorite brands (PSB) routinely makes speakers rated within their nominal bandwidth in the +/- 1dB range, but getting that in an anechoic chamber and in an actual room are two different things. Room correction can help a lot, but it can't fix giant "holes" in the response (i.e. you can turn down peaks much easier than correcting pits) so bass traps and other treatments might be necessary. But the notion that buying more expensive speakers will make it sound even better is flawed by the room as the same room will cause suck-out in the same bands save perhaps from some speciality speakers (Focal Whispers come to mind) that attempt to foil the room reflections, etc. within reason (even then the bass region can still be an issue). Now are you going to get better room response with $50k speakers? I find it doubtful. There are other measurements, but frequency response is a pretty good indicator of even response to my ears.
But if you have a really nice room, the response can be good even without room correction (I'm lucky to get +/- 5dB overall in my home theater, mostly due to some suckouts in bass where I'll need traps to even it out), but I have no such issues in my music room where the back of the room acts like trap on its own. The Carver AL-IIIs are only rated +/- 3dB to begin with and as you can see from the REW graph, it almost achieves that in the actual room. (red graph is where I actually like the bass set, which gives a smooth downward slope to flat, but I also took measurements with the active crossover set to flat on the green curve). With bass, it's +/- 5dB, but above 200Hz (ribbons only), it's +/- 3dB and without any room correction and those are dipoles. I've only come close with my home theater stereo mode recently after more treatments and room correction, I think it now sounds comparable in 2-channel (+/- 5dB overall, with most within +/- 2.5dB save the 680Hz dip; the graph is "reference" so it slides down over 10kHz, which I prefer to "flat" there).