I like you state as if it were a fact and not something that is pretty much just reliant on a matter of taste. Yes, it is almost gospel among a certain set of gamers the Wii is viewed as a ghost town to the PS360's wild west, but that this prevalent view is so dominant on the likes of message boards like this doesn't make it any more true.
The strongest hardware doesn't always sell the most? Does that somehow mean that the Wii's software catalogue is better than the 360s?
But as shown by the Wii itself, being comparatively under specced certainly didn't help in terms of providing an amazing breadth of software.
Yes, it did. There were tons of games that only appeared on the Wii precisely because it was easier to develop for. You think Kororinpa or Sin & Punishment 2 or Fragile would appear on the PS360? Those development teams did not and probably still don't have the resources to be able to do that.
Games like Kororinpa were relegated to a download ghetto by Microsoft and Sony, the idea that you could devote some serious resources to a package title like that and expect the same amount of compensation because the resulting product wasn't of any less quality in design than than a production that ran tens of millions of dollars may have died with the Wii.
Sin & Punishment 2 is only allowed because the last-gen graphics allowed for some measure of return on Nintendo's investment in picking Treasure's niche gems. The only way that would make it to market on PS360 would be if it were multiplayer heavy or of the artistic wankery.
Then you have Fragile, which is by a huge publisher, but a small game with less availability of the company's resources. Namco would never be crazy tp give a game like that enough of the development time it needed with a full team working on HD assets. Not in a million years.
And the Wii had gobs of this stuff, of course not all of it good, and of course more than a few titles of debatable quality. I know it gets overlooked because "LOL Wii," but that doesn't change the reality of the situation -- it just points to the tunnel vision of confirmation bias these people enjoy basking in.
Being the same level of power and fostering the same development path as the PS360 would have killed the Opoonas and Zack & Wikis and Hospitals and Tatsunoko vs. Capcoms dead before they even came to market. The gap between between downloadable titles and the major HD releases into a middle road of ambition that has been sustainable up to this point was entirely due to the Wii's hardware weakness giving it that advantage.
In fact the matter was so serious that out of the three major territories, one completely abandoned consoles as the main market and went to handhelds precisely because they offered less power and a richer development environment because of that.
Whether this generation bucks the not-so-weird-when-you-think-about-it remains to be seen, but quite apart from where the games I want to play appear, my heart will support the console maker whose platform gives the widest variety of developers the opportunity to shine, for whatever reason.