Happy Squirrel hit the nail on the head.
As he touches on, the problem was/is an institutional one: after all these publishers (and therefore developers, who follow where the money goes) invested very heavily in the idea of an HD future, pouring capital into technology, artists and programmers and then selling that to their shareholders as a cost of doing business, it becomes very difficult to have to turn around and admit that you've now sunk stunning amounts of cash into assets that are much less valuable than they were even a year ago (this isn't to say there isn't money in HD games, it's simply that there is the potential to make far more money with much less risk in the camp that, at best, they were benignly ignoring).
A case in point is Lost Colonies, a game that, by all counts, cost some 50 million after development and marketing were all said and done (I am assuming the cost of developing the engine was part of the price tag for the sake of this example). With that sort of expenditure, Capcom needs to get a *ton* of mileage out of that technology and if it isn't very scaleable it's going to be hard to recoup that investment when your assumptions going in were that you'd end up with 100 million (a number I'm throwing out for the sake of argument--it could be much higher or lower) HD consoles. Mind you, I'm not picking on Capcom, I'm just using them as one example of how things can go awry when the future you invested in turns out to be a mirage.
This is part of the reason you see so many publishers and developers lashing out at the Wii during "We Hate Wii" month: they invested so much time, money, effort, sweat, blood, virgins, etc. into a paradigm that is rapidly eroding that you're witnessing the real-time death throes of a lot of credibility and a lot of out-sized egos. When the smoke clears, though, most everyone is going to end up developing titles for Wii out of neccesity, regardless of whether any of them truly like or believe in it.
This, incidentally, also explains why a lot of professional gaming critics and fanboys for MS and Sony do the same: they staked their reps on the Wii being a trainwreck or, at best, a novelty that would quickly be relegated to an irrelevant third place, a suitable position for what they perceived to be "kiddie" or a "toy" or a "gimmick" (how soon they forget the lessons of the DS). Now that it's hammering the competition they're extracting every pound of flesh they can for being made to look foolish--making hay while the sun shines, in a manner of speaking.
Anyway, you needn't worry: there will be tons of software for the Wii, including 'real' games that will slowly shift the focus away from 'casual' titles and shovelware.