I'm not going to debate you on general economic theory, you seem to have a very good handle on it
However in my defence I'd point out that my argument has been centred upon the production of software for HD platforms, and how that relates to the other sectors of the industry. Not a global theory covering the manifold directions gaming has spidered into over the last few years.
So yeah, my point is a simplification but I believe its extremely pertinent and accurate one for the area in question.
Again its a matter of perspective. As a content-provider you simply deal with the technologies that are available to you. Refusing to deal with the additional challenge of moving from an SD to HD standard is like fighting the tide of history. You simply go where the money is presumed to be.
Which brings up the subject of Wii, a huge topic in itself which is why I'd hoped to avoid it if at all possible.
As you correctly pointed out Wii demonstrates that you don't need to reinvent the wheel graphically to create a market leading product. I totally agree.
However you can counter with the view that Wii's success was largely the product of it creating a new market, one that specifically responded to the novelty and accessibility of its user interface. Furthermore its equally arguable that the way it differed technologically from its competition essentially consigned it to become obsolete sooner than they did, and prevented it from enjoying the full benefit of third-party software franchises.
Despite it being cheaper to develop for, Wii saw no benefit in terms of third-party software support. Furthermore being unable to create a technologically competitive version of leading multi-platform franchises like CoD or GTA essentially prevented it from growing its user-base beyond what Nintendo themselves were offering
Absolutely, there are other factors, and I'm not intending to suggest the push for monopolistic competition / oligopoly is the only motivating factor for these major publishers. What I'm saying is that one of the major reasons third parties did not support the Wii was that it went strongly against the strategy these huge publishers had adopted -- to raise the barriers of entry to prevent competition from ever having a chance to threaten them.
The last time I looked at the publishers totals for the 360 (which was in 2010), Ubisoft/Take 2/Activision/EA were 88% of the retail software market. People say the 360 is good for "third parties," but what is really true is that it's good for the four or five biggest publishers in the world. This is also why there has been such an enormous exodus of independent developers to PC, iPhone, iPad, and Facebook/Browser gaming.
So with that in mind, this push for better technologies was one that these major publishers eagerly participated in. They clearly have had chances to bail out -- not just to the Wii, but to portable systems, to social gaming and to iOS -- and almost every one of those opportunities has been missed. In their absence, companies like Zynga, Gameloft, and Rovio have risen to extreme and rapid wealth thanks to the vacuum EA/Take 2/Ubisoft/Activision created and refused to fill. Again, this is not simply incompetent leadership; it's a deliberate attempt by major publishers to create an oligopoly a la the big three music labels, and crowd out smaller publishers from competing in the space they've created.
Which gets back to my point that if you look at things on a product scale, once a certain technological standard has been set for that genre, you simply can't put that genie back in the bottle.
I'm not sure this is true, but I could be convinced by it. Surely the DS's success in Japan is evidence that this isn't always true? Japan somehow managed to go from PS2->DS without any issue. Why does CS remain one of if not the most popular PC FPS, even when we've had a decade of games come out and best its graphical prowess? How is WoW still so popular when lots of MMOs have come out with better graphics since then?
Edit: upon further reflection, these examples seem fairly rare, and are almost non existent on the home console systems. So I certainly think what you're saying seems true on some platforms.