@phusis Great post! I also appreciate the thought about room calibration on such a "no flavorings" speaker like the Bluehorn. Honestly I didn't consider that in my thoughts and I should have never the less the reason I chose the Bluehorn as an example of studio speakers is because they are internally powered and the amps are designed for the speaker drivers individually there is no way to get to that level of accuracy buying amps and speakers that are not designed for each other. Also the speakers in a system that is trying to be accurate and not musical is spongy your brain will fill in the gaps of the music especially when you have more experience, most people have a few songs very well they know how that song sounds on different systems so when it sounds different on system A or B the experienced listener can very accurately note the differences compared to his reference, and if you listen for many many years you will also have a reference of where your reference system is accounting for it's particular deficiencies. Once again our brains are the listeners not our ears. Speakers don't have to be spongy they can be accurate simply turning the electrical signal into acoustic information. This is why there must be a baseline Wilson, Magico and the like are not flat they sound great but aren't flat, this is why you rarely see speakers with full range polar pattern test patterns like pro microphones come with. Professional speakers do come with these patters but not full frequency, even limited frequency polar patters are all over the place that's just the nature of the beast.
Room acoustics are secondary meaning other than using deep learning / AI in the near future to see the acoustic environment there is no standard because of that it isn't in the tool chest of audiophiles who are going for accurate stems to expect baseline acoustics from the manufactures built in DSP systems that is on the post playback side of the equation.
Also yes the price is very steep on the Bullhorns but the technology is so ahead of everything else that it was the right choice for looking at a system that was reference not economic. SSL and Pro Tools are very standard, SSL, Neive, Harrison are all very good names in mixers/ preamps but SSL is probably what most high end studios use. Of course there are boutique studios not unlike audiophile playback system and recording systems that are over the top crystal clear in every facet of the recording and playback but since the standard high end recording studio doesn't have that equipment it's like having 2x the headroom in a recording and not knowing how that will sound. This exact thing happened to cassette tape manufactures in the 80s, hi end companies make cassette playback machines that made all the prerecorded cassettes sound unlistenable because they revealed information that wasn't available in standard high end cassette tape recorders.