I think there are at least two different topics here and both are interesting:
1. Tuning systems and rooms: The two sides never seem to converge on this one, and I suggest it's due to the fact that audiophiles do not all have the same objective. I'm not sure why we have such a hard time admitting this as a basic assumption. Some audiophiles love this pursuit in order to enjoy the technological pursuit of "accurate" reproduction of what is on a recording... hearing every detail both additive and subtractive from the musical experience, because that's what the engineer laid down. To them, tweaking and tuning to make mediocre recordings sound musical is antithetical to why they are in this hobby in the first place. The second type -- and yes there are undoubtedly more than two, but to oversimplify -- are those who want to fool their brains into thinking a live musical event is playing out in their listening room, so they can experience at least a part of the emotional experience of what the musician played/intended. When a Type 2 like Michael (or me) starts talking about making adjustments to make a higher percentage of recordings fool our brains, it necessarily will never make sense to Type 1, unless/until that Type 1 person might experience it for themselves, and maybe if they are at heart a music lover, they might just shift their overall objective.
In the meantime, we should could avoid a lot of argument by being clear about our objective going in, and only if the objectives align is it worth the ink to argue about the means to achieve it. But even if we are ships passing in the night, there is some entertainment value trying to convince one another our objective is the more worthy! It's been fueling audio forums for decades.
2. Vintage equipment vs modern: I would respectfully suggest we restage this question along the lines of my #1 above. I don't think it's so much about old vs new, and it is about designers who design for Type 1's vs those that design for Type 2's. My short response to the original question is in line with Michael Green's, in that speakers of old seemed to be more about musicality, as driven by the ears of the designers, whereas today's speakers, while some are indeed designed around musicality and a designer's great ears like the old days, are the result of several forces I've noticed: a) Reviewers, somewhere along the line ... and maybe it coincided with the digital revolution ... started assigning badges of honor to attributes like "neutrality" and "accuracy" which, in an epic twist of fate, have no objective meaning whatsoever. I observe these terms have come to connote sparkling, airy highs and a thin midrange, uncolored by any chestiness, richness or humanity. IMHO the whole neutrality juggernaut has fueled a generation of products and listeners who unfortunately are missing out on the miracle of our hobby... that a system can truly trip the wires in our brains that create the illusion of real music. "Neutral" systems are amazing technological reproducers of sound and cause one to instantly say "Wow that's a great system." Musical systems cause one to instantly tap their foot and say "Wow Miles Davis is great." So audio companies face a customer base in which 80% of them want neutral hifi. What is a business that wants to stay in business to do? Many (not all) lean toward hifi.
As was pointed out earlier in this thread, there is no need to create false, judgmental distinctions between tuning a room, tuning with an equalizer, tuning with a cable, and tuning by choosing a component like a DAC or power amplifier. Every choice we make tunes our systems. Our entire hobby is about tuning!
I don't understand what Michael Green is getting at with his "codes" references, but I do wholeheartedly agree that anything that can be done to a room or stereo system to improve the probability that our little reptile brains will be fooled into thinking they are listening to live music is a very, very good thing. But then again I am a Type 2!
