I get the idea of tuning as an ongoing project, but I doubt that things you mentioned about High End Audio were that deliberate and wise product of a big conspiracy. More likely that someone jumped on the opportunity. Take your example of power cords that became detached. How many of the manufacturers of "boxes" started marketing their aftermarket power cords at that time? I am not sure that even today, decades later, there is a flood of power cords from manufacturers of amplifiers.
What you seem to neglect in your approach is that many people do have more concerns than sound and windmills. Making a perfect room, stands, springs, whatever, is all fine but people have jobs, children to take to ballet classes, and dogs roaming the living room. For them, convenience accounts for lot. If they can change the sound by buying new piece of equipment instead of rearranging a living space and that over a long time, they are willing to accept a trade off. They have no time and energy to move things around a few times a day, or ever. And they do not feel scammed. Price is sometimes smaller factor that it seems at first.
Those who enjoy their world of tuning must be a happy bunch. Nothing wrong with doing it and I am sure results may be great. It is just that it is not for everyone.
Banana plugs are, for some of us, wonderful invention. Neat, convenient, perfect. Maybe there is some loss of audio quality for those who do not mind wires sticking out, but for the rest of us banana plugs are just fine. Whoever invented them does deserve whatever money she/he made with it. Theoretical discussions about why they are bad are great and may lead to improvement, but in practice, many people prefer them. Not because they got fooled by HEA industry.