Interesting theory you have there...
But, I am going to have to disagree...
Anyway, I don't think you can compare SACD/DVD-A & BR either. For several reasons:
1. Systems - To notice a real benefit from going with a SACD/DVD-A over CD you need to have a good listening system. Most people have a HTIB, Crappy Speakers, BOSE, TV Speaker, or other systems that wouldn't allow them to enjoy the benefits at all. This being said, why would someone go out and buy a SACD/DVD-A Player if on their system the listener can't pick out the difference between a 192kHz/24bit track and a 44.1kHz/16 bit track. With BR and HD Video it is rather easy to see the difference between 480p and 1080p even on a middle of the road TV.
2. Cost - The cost of many SACD/DVD-A Players when they first came out was in the $800-$1200 range, and they stayed there for a while. When you can go out and pick up a BR player for $399 (about the same as some of the original DVD Players) it makes more sense.
3. Availability - I don't know if you have ever been SACD/DVD-A shopping, but, they were hard to find at the apex of the trend. HD-Video is easy to find. Wal-Mart, Target, BB, CC, almost every internet retailer has inventory, end caps, and adds. The product is right there in your face.
4. HD Audio v. HD Video - Today most of people listen to MP3s, many ripped at very poor rates. The mass of music consumers want cheap, easy to use, downloadable to the iPod music. If many do buy CDs they want to stick it in the computer have iTunes rip it and add it to the iPod, putting the CD on the shelf to collect dust or ride around in their car. There is no push for HD Audio. HD-Video however is completely different. Watch TV some night and see how many adds there are about "HD Cables is better than Dish", "DirectTV HD is the best", "Locals on HD", "Discovery HD theater in stunning 1080i, join Club 1080 Now", "Now in HD", "Cincinnati's only News in HD". There is a MASSIVE push for everything video to be in HD. How many Standard Definition Televisions do you see when you go to the store. Almost none compared to the number of HD, 720p, 1080i, 1080p, Full HD, TVs (or whatever the marketing calls them). While what do you see in the consumer store Audio wise? iPod, Zune, HTIB, BOSE, maybe Klipsch or Polk. I think this is a big big difference.